diff --git a/src/bootsupport/modules/punk/mix/templates-0.2.0.tm b/src/bootsupport/modules/punk/mix/templates-0.2.0.tm
index cdac3694..839bb06d 100644
Binary files a/src/bootsupport/modules/punk/mix/templates-0.2.0.tm and b/src/bootsupport/modules/punk/mix/templates-0.2.0.tm differ
diff --git a/src/modules/punk/mix/#modpod-templates-999999.0a1.0/templates/project_layouts/vendor/punk/project-0.1/src/make.tcl b/src/modules/punk/mix/#modpod-templates-999999.0a1.0/templates/project_layouts/vendor/punk/project-0.1/src/make.tcl
index df240826..894dcba5 100644
--- a/src/modules/punk/mix/#modpod-templates-999999.0a1.0/templates/project_layouts/vendor/punk/project-0.1/src/make.tcl
+++ b/src/modules/punk/mix/#modpod-templates-999999.0a1.0/templates/project_layouts/vendor/punk/project-0.1/src/make.tcl
@@ -3287,6 +3287,60 @@ proc ::punkboot::get_src_provenance_warnings {projectroot label} {
     set checked_vcs_roots [dict create]
     return [list 1 [::punkboot::utils::vcs_dirty_warnings $projectroot checked_vcs_roots $label src]]
 }
+#Replace a file that may be MEMORY-MAPPED by another process (or by this one).
+#
+#On windows an ordinary 'file copy -force' onto a mapped file is refused: a zipfs mount
+#maps its archive (tclZipfs.c CreateFileMappingW + MapViewOfFile), so a zip-based .tm
+#modpod that any running shell - including this build - has mounted cannot be overwritten
+#in place. Windows reports ERROR_USER_MAPPED_FILE (1224); Tcl's Tcl_WinConvertError maps
+#only Win32 codes 0..267 and sends everything above them to EINVAL, so it surfaces as the
+#uninformative "invalid argument" (same code in 8.6 and 9.x).
+#
+#UNLINKING a mapped file IS allowed - the holder keeps reading its own mapping and new
+#content lands at the name - so delete-then-place succeeds where overwrite cannot. The new
+#content goes to a sibling temp FIRST so a mid-sequence failure can never leave the target
+#missing.
+#
+#Returns one of: ok (plain copy worked), replaced (needed the delete-then-place path),
+#failed (target untouched), broken (target was unlinked and could not be restored - the
+#caller must treat this as serious). The first copy's error message is written to the
+#variable named by firsterrvar.
+proc ::punkboot::replace_possibly_mapped_file {srcfile tgtfile firsterrvar} {
+    upvar 1 $firsterrvar firsterr
+    set firsterr ""
+    if {![catch {file copy -force $srcfile $tgtfile} firsterr]} {
+        return ok
+    }
+    if {![file exists $tgtfile]} {
+        #nothing to unlink - whatever failed, it was not an in-place overwrite
+        return failed
+    }
+    set tmpfile $tgtfile.punkboot-new
+    catch {file delete -force -- $tmpfile}
+    if {[catch {file copy -- $srcfile $tmpfile}]} {
+        catch {file delete -force -- $tmpfile}
+        return failed
+    }
+    if {[catch {file delete -- $tgtfile}]} {
+        catch {file delete -force -- $tmpfile}
+        return failed
+    }
+    if {[catch {file rename -- $tmpfile $tgtfile}]} {
+        return broken
+    }
+    return replaced
+}
+#Actionable text for a file-operation failure whose message is windows' catch-all.
+#Returns "" when the error does not look like that case.
+proc ::punkboot::mapped_file_hint {errmsg tgtfile} {
+    if {![string match -nocase "*invalid argument*" $errmsg]} {
+        return ""
+    }
+    return "'invalid argument' is Tcl's catch-all for any windows error above 267 (Tcl_WinConvertError), not a bad argument.\
+        For a file replace the usual cause is ERROR_USER_MAPPED_FILE: '$tgtfile' is memory-mapped by a process that has it mounted -\
+        a zipfs/modpod mount does this, so a running punk shell (or this build) holding that .tm blocks an in-place overwrite.\
+        Close shells holding it, or rerun - the update now replaces such files by delete-then-place rather than overwrite."
+}
 #Availability probe + boot-precondition check of an assembled kit vfs (G-125), shared by the
 #kit gate in the bake loop and the 'check' command report. Same guarded-require treatment as
 #the provenance check above: a stale or missing punkboot::utils snapshot must not brick the
@@ -4370,31 +4424,47 @@ if {$::punkboot::command eq "bootsupport"} {
                                     $boot_event targetset_started
                                     # -- --- --- --- --- ---
                                     puts "\nBOOTSUPPORT module$which update: $srcfile -> $tgtfile"
-                                    if {[catch {
-                                        file copy -force $srcfile  $tgtfile
-                                    } errM]} {
-                                        #a copy onto a modpod this make.tcl process has mounted (e.g punk::mix::templates)
-                                        #fails on windows even when the target content is already current (a prior failed
-                                        #record forces a retry). If content is already identical, record OK so the record
-                                        #converges instead of churning FAILED forever.
-                                        set already_current 0
-                                        if {[file exists $tgtfile] && [file size $tgtfile] == [file size $srcfile]} {
-                                            catch {
-                                                set src_ck [dict get [punk::mix::base::lib::cksum_path $srcfile] cksum]
-                                                set tgt_ck [dict get [punk::mix::base::lib::cksum_path $tgtfile] cksum]
-                                                if {$src_ck ne "" && $src_ck eq $tgt_ck} {
-                                                    set already_current 1
-                                                }
-                                            }
+                                    #An in-place overwrite is refused when the target is memory-mapped -
+                                    #which is what a mounted zip-based .tm modpod (e.g punk::mix::templates)
+                                    #is. replace_possibly_mapped_file falls back to delete-then-place, which
+                                    #windows does allow. See its comment for why the error reads "invalid
+                                    #argument" and why unlinking is safe for the process holding the mapping.
+                                    switch -- [::punkboot::replace_possibly_mapped_file $srcfile $tgtfile errM] {
+                                        ok {
+                                            $boot_event targetset_end OK
+                                        }
+                                        replaced {
+                                            puts stdout "  (in-place overwrite refused - replaced by delete-then-place; target was memory-mapped, e.g a mounted modpod)"
+                                            $boot_event targetset_end OK -note "overwrite refused ($errM) - replaced via delete-then-place (target memory-mapped)"
                                         }
-                                        if {$already_current} {
-                                            $boot_event targetset_end OK -note "copy failed ($errM) but target content already identical (self-mounted modpod?)"
-                                        } else {
-                                            puts stderr "BOOTSUPPORT module$which update FAILED: $tgtfile ($errM)"
+                                        broken {
+                                            puts stderr "BOOTSUPPORT module$which update FAILED: $tgtfile was unlinked and could not be replaced - restore it from $srcfile by hand ($errM)"
                                             $boot_event targetset_end FAILED
                                         }
-                                    } else {
-                                        $boot_event targetset_end OK
+                                        default {
+                                            #target untouched. If its content is already identical, record OK so a
+                                            #prior failed record converges instead of churning FAILED forever.
+                                            set already_current 0
+                                            if {[file exists $tgtfile] && [file size $tgtfile] == [file size $srcfile]} {
+                                                catch {
+                                                    set src_ck [dict get [punk::mix::base::lib::cksum_path $srcfile] cksum]
+                                                    set tgt_ck [dict get [punk::mix::base::lib::cksum_path $tgtfile] cksum]
+                                                    if {$src_ck ne "" && $src_ck eq $tgt_ck} {
+                                                        set already_current 1
+                                                    }
+                                                }
+                                            }
+                                            if {$already_current} {
+                                                $boot_event targetset_end OK -note "copy failed ($errM) but target content already identical"
+                                            } else {
+                                                puts stderr "BOOTSUPPORT module$which update FAILED: $tgtfile ($errM)"
+                                                set _hint [::punkboot::mapped_file_hint $errM $tgtfile]
+                                                if {$_hint ne ""} {
+                                                    puts stderr "  $_hint"
+                                                }
+                                                $boot_event targetset_end FAILED
+                                            }
+                                        }
                                     }
                                     # -- --- --- --- --- ---
                                 } else {
diff --git a/src/project_layouts/vendor/punk/basic/src/make.tcl b/src/project_layouts/vendor/punk/basic/src/make.tcl
index df240826..894dcba5 100644
--- a/src/project_layouts/vendor/punk/basic/src/make.tcl
+++ b/src/project_layouts/vendor/punk/basic/src/make.tcl
@@ -3287,6 +3287,60 @@ proc ::punkboot::get_src_provenance_warnings {projectroot label} {
     set checked_vcs_roots [dict create]
     return [list 1 [::punkboot::utils::vcs_dirty_warnings $projectroot checked_vcs_roots $label src]]
 }
+#Replace a file that may be MEMORY-MAPPED by another process (or by this one).
+#
+#On windows an ordinary 'file copy -force' onto a mapped file is refused: a zipfs mount
+#maps its archive (tclZipfs.c CreateFileMappingW + MapViewOfFile), so a zip-based .tm
+#modpod that any running shell - including this build - has mounted cannot be overwritten
+#in place. Windows reports ERROR_USER_MAPPED_FILE (1224); Tcl's Tcl_WinConvertError maps
+#only Win32 codes 0..267 and sends everything above them to EINVAL, so it surfaces as the
+#uninformative "invalid argument" (same code in 8.6 and 9.x).
+#
+#UNLINKING a mapped file IS allowed - the holder keeps reading its own mapping and new
+#content lands at the name - so delete-then-place succeeds where overwrite cannot. The new
+#content goes to a sibling temp FIRST so a mid-sequence failure can never leave the target
+#missing.
+#
+#Returns one of: ok (plain copy worked), replaced (needed the delete-then-place path),
+#failed (target untouched), broken (target was unlinked and could not be restored - the
+#caller must treat this as serious). The first copy's error message is written to the
+#variable named by firsterrvar.
+proc ::punkboot::replace_possibly_mapped_file {srcfile tgtfile firsterrvar} {
+    upvar 1 $firsterrvar firsterr
+    set firsterr ""
+    if {![catch {file copy -force $srcfile $tgtfile} firsterr]} {
+        return ok
+    }
+    if {![file exists $tgtfile]} {
+        #nothing to unlink - whatever failed, it was not an in-place overwrite
+        return failed
+    }
+    set tmpfile $tgtfile.punkboot-new
+    catch {file delete -force -- $tmpfile}
+    if {[catch {file copy -- $srcfile $tmpfile}]} {
+        catch {file delete -force -- $tmpfile}
+        return failed
+    }
+    if {[catch {file delete -- $tgtfile}]} {
+        catch {file delete -force -- $tmpfile}
+        return failed
+    }
+    if {[catch {file rename -- $tmpfile $tgtfile}]} {
+        return broken
+    }
+    return replaced
+}
+#Actionable text for a file-operation failure whose message is windows' catch-all.
+#Returns "" when the error does not look like that case.
+proc ::punkboot::mapped_file_hint {errmsg tgtfile} {
+    if {![string match -nocase "*invalid argument*" $errmsg]} {
+        return ""
+    }
+    return "'invalid argument' is Tcl's catch-all for any windows error above 267 (Tcl_WinConvertError), not a bad argument.\
+        For a file replace the usual cause is ERROR_USER_MAPPED_FILE: '$tgtfile' is memory-mapped by a process that has it mounted -\
+        a zipfs/modpod mount does this, so a running punk shell (or this build) holding that .tm blocks an in-place overwrite.\
+        Close shells holding it, or rerun - the update now replaces such files by delete-then-place rather than overwrite."
+}
 #Availability probe + boot-precondition check of an assembled kit vfs (G-125), shared by the
 #kit gate in the bake loop and the 'check' command report. Same guarded-require treatment as
 #the provenance check above: a stale or missing punkboot::utils snapshot must not brick the
@@ -4370,31 +4424,47 @@ if {$::punkboot::command eq "bootsupport"} {
                                     $boot_event targetset_started
                                     # -- --- --- --- --- ---
                                     puts "\nBOOTSUPPORT module$which update: $srcfile -> $tgtfile"
-                                    if {[catch {
-                                        file copy -force $srcfile  $tgtfile
-                                    } errM]} {
-                                        #a copy onto a modpod this make.tcl process has mounted (e.g punk::mix::templates)
-                                        #fails on windows even when the target content is already current (a prior failed
-                                        #record forces a retry). If content is already identical, record OK so the record
-                                        #converges instead of churning FAILED forever.
-                                        set already_current 0
-                                        if {[file exists $tgtfile] && [file size $tgtfile] == [file size $srcfile]} {
-                                            catch {
-                                                set src_ck [dict get [punk::mix::base::lib::cksum_path $srcfile] cksum]
-                                                set tgt_ck [dict get [punk::mix::base::lib::cksum_path $tgtfile] cksum]
-                                                if {$src_ck ne "" && $src_ck eq $tgt_ck} {
-                                                    set already_current 1
-                                                }
-                                            }
+                                    #An in-place overwrite is refused when the target is memory-mapped -
+                                    #which is what a mounted zip-based .tm modpod (e.g punk::mix::templates)
+                                    #is. replace_possibly_mapped_file falls back to delete-then-place, which
+                                    #windows does allow. See its comment for why the error reads "invalid
+                                    #argument" and why unlinking is safe for the process holding the mapping.
+                                    switch -- [::punkboot::replace_possibly_mapped_file $srcfile $tgtfile errM] {
+                                        ok {
+                                            $boot_event targetset_end OK
+                                        }
+                                        replaced {
+                                            puts stdout "  (in-place overwrite refused - replaced by delete-then-place; target was memory-mapped, e.g a mounted modpod)"
+                                            $boot_event targetset_end OK -note "overwrite refused ($errM) - replaced via delete-then-place (target memory-mapped)"
                                         }
-                                        if {$already_current} {
-                                            $boot_event targetset_end OK -note "copy failed ($errM) but target content already identical (self-mounted modpod?)"
-                                        } else {
-                                            puts stderr "BOOTSUPPORT module$which update FAILED: $tgtfile ($errM)"
+                                        broken {
+                                            puts stderr "BOOTSUPPORT module$which update FAILED: $tgtfile was unlinked and could not be replaced - restore it from $srcfile by hand ($errM)"
                                             $boot_event targetset_end FAILED
                                         }
-                                    } else {
-                                        $boot_event targetset_end OK
+                                        default {
+                                            #target untouched. If its content is already identical, record OK so a
+                                            #prior failed record converges instead of churning FAILED forever.
+                                            set already_current 0
+                                            if {[file exists $tgtfile] && [file size $tgtfile] == [file size $srcfile]} {
+                                                catch {
+                                                    set src_ck [dict get [punk::mix::base::lib::cksum_path $srcfile] cksum]
+                                                    set tgt_ck [dict get [punk::mix::base::lib::cksum_path $tgtfile] cksum]
+                                                    if {$src_ck ne "" && $src_ck eq $tgt_ck} {
+                                                        set already_current 1
+                                                    }
+                                                }
+                                            }
+                                            if {$already_current} {
+                                                $boot_event targetset_end OK -note "copy failed ($errM) but target content already identical"
+                                            } else {
+                                                puts stderr "BOOTSUPPORT module$which update FAILED: $tgtfile ($errM)"
+                                                set _hint [::punkboot::mapped_file_hint $errM $tgtfile]
+                                                if {$_hint ne ""} {
+                                                    puts stderr "  $_hint"
+                                                }
+                                                $boot_event targetset_end FAILED
+                                            }
+                                        }
                                     }
                                     # -- --- --- --- --- ---
                                 } else {
diff --git a/src/project_layouts/vendor/punk/project-0.1/src/make.tcl b/src/project_layouts/vendor/punk/project-0.1/src/make.tcl
index df240826..894dcba5 100644
--- a/src/project_layouts/vendor/punk/project-0.1/src/make.tcl
+++ b/src/project_layouts/vendor/punk/project-0.1/src/make.tcl
@@ -3287,6 +3287,60 @@ proc ::punkboot::get_src_provenance_warnings {projectroot label} {
     set checked_vcs_roots [dict create]
     return [list 1 [::punkboot::utils::vcs_dirty_warnings $projectroot checked_vcs_roots $label src]]
 }
+#Replace a file that may be MEMORY-MAPPED by another process (or by this one).
+#
+#On windows an ordinary 'file copy -force' onto a mapped file is refused: a zipfs mount
+#maps its archive (tclZipfs.c CreateFileMappingW + MapViewOfFile), so a zip-based .tm
+#modpod that any running shell - including this build - has mounted cannot be overwritten
+#in place. Windows reports ERROR_USER_MAPPED_FILE (1224); Tcl's Tcl_WinConvertError maps
+#only Win32 codes 0..267 and sends everything above them to EINVAL, so it surfaces as the
+#uninformative "invalid argument" (same code in 8.6 and 9.x).
+#
+#UNLINKING a mapped file IS allowed - the holder keeps reading its own mapping and new
+#content lands at the name - so delete-then-place succeeds where overwrite cannot. The new
+#content goes to a sibling temp FIRST so a mid-sequence failure can never leave the target
+#missing.
+#
+#Returns one of: ok (plain copy worked), replaced (needed the delete-then-place path),
+#failed (target untouched), broken (target was unlinked and could not be restored - the
+#caller must treat this as serious). The first copy's error message is written to the
+#variable named by firsterrvar.
+proc ::punkboot::replace_possibly_mapped_file {srcfile tgtfile firsterrvar} {
+    upvar 1 $firsterrvar firsterr
+    set firsterr ""
+    if {![catch {file copy -force $srcfile $tgtfile} firsterr]} {
+        return ok
+    }
+    if {![file exists $tgtfile]} {
+        #nothing to unlink - whatever failed, it was not an in-place overwrite
+        return failed
+    }
+    set tmpfile $tgtfile.punkboot-new
+    catch {file delete -force -- $tmpfile}
+    if {[catch {file copy -- $srcfile $tmpfile}]} {
+        catch {file delete -force -- $tmpfile}
+        return failed
+    }
+    if {[catch {file delete -- $tgtfile}]} {
+        catch {file delete -force -- $tmpfile}
+        return failed
+    }
+    if {[catch {file rename -- $tmpfile $tgtfile}]} {
+        return broken
+    }
+    return replaced
+}
+#Actionable text for a file-operation failure whose message is windows' catch-all.
+#Returns "" when the error does not look like that case.
+proc ::punkboot::mapped_file_hint {errmsg tgtfile} {
+    if {![string match -nocase "*invalid argument*" $errmsg]} {
+        return ""
+    }
+    return "'invalid argument' is Tcl's catch-all for any windows error above 267 (Tcl_WinConvertError), not a bad argument.\
+        For a file replace the usual cause is ERROR_USER_MAPPED_FILE: '$tgtfile' is memory-mapped by a process that has it mounted -\
+        a zipfs/modpod mount does this, so a running punk shell (or this build) holding that .tm blocks an in-place overwrite.\
+        Close shells holding it, or rerun - the update now replaces such files by delete-then-place rather than overwrite."
+}
 #Availability probe + boot-precondition check of an assembled kit vfs (G-125), shared by the
 #kit gate in the bake loop and the 'check' command report. Same guarded-require treatment as
 #the provenance check above: a stale or missing punkboot::utils snapshot must not brick the
@@ -4370,31 +4424,47 @@ if {$::punkboot::command eq "bootsupport"} {
                                     $boot_event targetset_started
                                     # -- --- --- --- --- ---
                                     puts "\nBOOTSUPPORT module$which update: $srcfile -> $tgtfile"
-                                    if {[catch {
-                                        file copy -force $srcfile  $tgtfile
-                                    } errM]} {
-                                        #a copy onto a modpod this make.tcl process has mounted (e.g punk::mix::templates)
-                                        #fails on windows even when the target content is already current (a prior failed
-                                        #record forces a retry). If content is already identical, record OK so the record
-                                        #converges instead of churning FAILED forever.
-                                        set already_current 0
-                                        if {[file exists $tgtfile] && [file size $tgtfile] == [file size $srcfile]} {
-                                            catch {
-                                                set src_ck [dict get [punk::mix::base::lib::cksum_path $srcfile] cksum]
-                                                set tgt_ck [dict get [punk::mix::base::lib::cksum_path $tgtfile] cksum]
-                                                if {$src_ck ne "" && $src_ck eq $tgt_ck} {
-                                                    set already_current 1
-                                                }
-                                            }
+                                    #An in-place overwrite is refused when the target is memory-mapped -
+                                    #which is what a mounted zip-based .tm modpod (e.g punk::mix::templates)
+                                    #is. replace_possibly_mapped_file falls back to delete-then-place, which
+                                    #windows does allow. See its comment for why the error reads "invalid
+                                    #argument" and why unlinking is safe for the process holding the mapping.
+                                    switch -- [::punkboot::replace_possibly_mapped_file $srcfile $tgtfile errM] {
+                                        ok {
+                                            $boot_event targetset_end OK
+                                        }
+                                        replaced {
+                                            puts stdout "  (in-place overwrite refused - replaced by delete-then-place; target was memory-mapped, e.g a mounted modpod)"
+                                            $boot_event targetset_end OK -note "overwrite refused ($errM) - replaced via delete-then-place (target memory-mapped)"
                                         }
-                                        if {$already_current} {
-                                            $boot_event targetset_end OK -note "copy failed ($errM) but target content already identical (self-mounted modpod?)"
-                                        } else {
-                                            puts stderr "BOOTSUPPORT module$which update FAILED: $tgtfile ($errM)"
+                                        broken {
+                                            puts stderr "BOOTSUPPORT module$which update FAILED: $tgtfile was unlinked and could not be replaced - restore it from $srcfile by hand ($errM)"
                                             $boot_event targetset_end FAILED
                                         }
-                                    } else {
-                                        $boot_event targetset_end OK
+                                        default {
+                                            #target untouched. If its content is already identical, record OK so a
+                                            #prior failed record converges instead of churning FAILED forever.
+                                            set already_current 0
+                                            if {[file exists $tgtfile] && [file size $tgtfile] == [file size $srcfile]} {
+                                                catch {
+                                                    set src_ck [dict get [punk::mix::base::lib::cksum_path $srcfile] cksum]
+                                                    set tgt_ck [dict get [punk::mix::base::lib::cksum_path $tgtfile] cksum]
+                                                    if {$src_ck ne "" && $src_ck eq $tgt_ck} {
+                                                        set already_current 1
+                                                    }
+                                                }
+                                            }
+                                            if {$already_current} {
+                                                $boot_event targetset_end OK -note "copy failed ($errM) but target content already identical"
+                                            } else {
+                                                puts stderr "BOOTSUPPORT module$which update FAILED: $tgtfile ($errM)"
+                                                set _hint [::punkboot::mapped_file_hint $errM $tgtfile]
+                                                if {$_hint ne ""} {
+                                                    puts stderr "  $_hint"
+                                                }
+                                                $boot_event targetset_end FAILED
+                                            }
+                                        }
                                     }
                                     # -- --- --- --- --- ---
                                 } else {
diff --git a/src/vfs/_vfscommon.vfs/modules/punk/mix/templates-0.2.0.tm b/src/vfs/_vfscommon.vfs/modules/punk/mix/templates-0.2.0.tm
index cdac3694..839bb06d 100644
Binary files a/src/vfs/_vfscommon.vfs/modules/punk/mix/templates-0.2.0.tm and b/src/vfs/_vfscommon.vfs/modules/punk/mix/templates-0.2.0.tm differ