diff --git a/.github/workflows/release.yml b/.github/workflows/release.yml
index f04ec43b0b2..f786193a6f2 100644
--- a/.github/workflows/release.yml
+++ b/.github/workflows/release.yml
@@ -37,6 +37,10 @@ on:
         description: 'File name prefix'
         required: false
         default: 'slacko64'
+      unionfs:
+        description: 'Layered file system, aufs or overlay'
+        required: false
+        default: 'aufs'
 
 jobs:
   build:
@@ -71,6 +75,8 @@ jobs:
       run: sudo sed -i s/^DISTRO_VERSION=.*/DISTRO_VERSION=${{ github.event.inputs.version }}/ ../woof-out_*/DISTRO_SPECS
     - name: Set file name prefix
       run: sudo sed -i s/^DISTRO_FILE_PREFIX=.*/DISTRO_FILE_PREFIX=${{ github.event.inputs.prefix }}/ ../woof-out_*/DISTRO_SPECS
+    - name: Set layered file system
+      run: echo "UNIONFS=${{ github.event.inputs.unionfs }}" | sudo tee -a ../woof-out_*/_00build_2.conf
     - name: 0setup
       run: |
         cd ../woof-out_*
diff --git a/initrd-progs/0initrd/README.txt b/initrd-progs/0initrd/README.txt
index 7cbcbdbecb8..0ffb34fbf00 100644
--- a/initrd-progs/0initrd/README.txt
+++ b/initrd-progs/0initrd/README.txt
@@ -136,6 +136,11 @@ psubdir=</path/to/install/directory>
    If a leading "/" is not provided, init will add it.
    This is the default path for locating any puppy file and any partition.
 
+punionfs=<aufs|overlay>
+   Overrides the union file system choice made at build time.
+   Use with care, as aufs and overlay are incompatible with each other.
+   To switch from aufs to overlay or vice versa, start with a fresh save layer (pfix=ram).
+
 ------------------------------------------------------------
 pupsfs=<partition> Specifies the puppy...sfs partition
 zdrv=<partition>   Specifies the zdrv...sfs  partition
diff --git a/initrd-progs/0initrd/init b/initrd-progs/0initrd/init
index dd77b07d7bc..2015fbdb01f 100755
--- a/initrd-progs/0initrd/init
+++ b/initrd-progs/0initrd/init
@@ -42,7 +42,7 @@ L_ERR_ONEPART_MOUNT_SFS_FAILED="%s %s mount of sfs failed." #printf
 L_ERR_AUFS_SFS_FAILED="aufs mount of %s failed." #printf
 L_ERR_TYPE_PUPSAVE="Type a number to choose which personal file to use:"
 L_DROPPED_TO_INITRD_SHELL="Dropped to initramfs shell. Type 'exec switch' to continue booting Puppy."
-L_SWITCH_ROOT="Performing a 'switch_root' to the layered filesystem..."
+L_SWITCH_ROOT="Performing a 'switch_root' to the %s filesystem..." #printf
 L_FOLDER_MARKED_BAD="Folder %s marked bad." #printf
 L_0_NONE="0  none"
 L_ERROR_FAILED_AUFS_STACK='Failed to create empty aufs stack'
@@ -105,6 +105,9 @@ LINUXFSLIST="ext2|ext3|ext4|btrfs|minix|f2fs|reiserfs"
 #Filesystem to be fsck
 FSCKLIST="ext2|ext3|ext4|vfat|msdos|exfat"
 
+# Layered file system to use
+UNIONFS='aufs'
+
 #=============================================================
 #                        FUNCTIONS
 #=============================================================
@@ -294,8 +297,10 @@ ensure_save_mounted() {
   if [ "$ONE_MP" != "$SAVE_MP" ];then
    #ensure SAVEPART is mounted on /mnt/dev_save
    [ -d "$SAVE_MP" ] || mkdir -p $SAVE_MP
-   echo "mount -o move $ONE_MP $SAVE_MP" #debug
-   mount -o move $ONE_MP $SAVE_MP
+   OPT="move"
+   [ "$UNIONFS" = 'overlay' ] && OPT="bind"
+   echo "mount -o $OPT $ONE_MP $SAVE_MP" #debug
+   mount -o $OPT $ONE_MP $SAVE_MP
   fi
   SAVE_FS="$ONE_FS"
  else
@@ -306,6 +311,7 @@ ensure_save_mounted() {
 find_drv_file() {
 # "$1" - specified filename - ex: /pup/mydrv-1.2.3.sfs
 # "$2" - default filename - ex: adrv_tahr_6.0.5.sfs
+# "$3" - look under root too - ex. 1
  ONE_FN=""
  [ "${1}" ] || [ "${2}" ] || return
  if [ "${1}" ];then
@@ -315,6 +321,7 @@ find_drv_file() {
   esac
  else
   ONE_TRY_FN="${PSUBDIR}/${2}"
+  [ "$3" -a ! -e "${ONE_MP}${ONE_TRY_FN}" ] && ONE_TRY_FN="/$2"
  fi
  if [ -L "${ONE_MP}${ONE_TRY_FN}" ];then
    C_MP="$(readlink -f "$ONE_MP")"
@@ -329,6 +336,7 @@ find_onepupdrv() {
 # "$2" - specified filename - ex: /pup/mydrv-1.2.3.sfs
 # "$3" - default filename - ex: adrv_tahr_6.0.5.sfs
 # "$4" - prefix for "drv" mountpoint - ex: a
+# "$5" - look under root too - ex. 1
  ONE_FN=""
  [ "${2}" ] || [ "${3}" ] || return
  [ "${4}" ] || return
@@ -340,7 +348,7 @@ find_onepupdrv() {
  [ "$ONE_PART" ] || return
  ensure_mounted "$ONE_PART" "/mnt/${4}drv"
  [ "$ONE_MP" ] || return
- find_drv_file "${2}" "${3}"
+ find_drv_file "${2}" "${3}" "${5}"
  [ "$ONE_FN" = "" -a "${2}" ] && echo "$ONE_PART, $ONE_TRY_FN file not found."
 }
 
@@ -423,14 +431,31 @@ setup_onepupdrv() {
  if ! [ "$ONE_LAYER" ] ; then
    return 4 #sfs mount failed
  fi
- if [ "$ONE_PREP" ];then
-  echo "mount -o remount,add:1:$ONE_LAYER /pup_new" #debug
-  mount -o remount,add:1:$ONE_LAYER /pup_new
+ if [ -n "$punionfs" ]; then
+  UNIONFS="$punionfs"
+ elif [ -f $SFS_MP/etc/rc.d/PUPSTATE ]; then
+  . $SFS_MP/etc/rc.d/PUPSTATE
+  [ -n "$PUNIONFS" ] && UNIONFS="$PUNIONFS"
+ fi
+ if [ "$UNIONFS" = 'overlay' ]; then
+  remount_overlay -e "s~lowerdir=([^,]+)~lowerdir=${SFS_MP}:\1~" -e "s~lowerdir=,~lowerdir=${SFS_MP},~"
   [ $? -eq 0 ] || return 5
  else
-  echo "mount -o remount,append:$ONE_LAYER /pup_new" #debug
-  mount -o remount,append:$ONE_LAYER /pup_new
-  [ $? -eq 0 ] || return 5
+  mountpoint -q /pup_new
+  if [ $? -ne 0 ];then
+   echo "mount -t aufs -o udba=reval,diropq=w,br=/mnt/tmpfs/pup_rw=rw,xino=/mnt/tmpfs/.aufs.xino unionfs /pup_new" #debug
+   mount -t aufs -o udba=reval,diropq=w,br=/mnt/tmpfs/pup_rw=rw,xino=/mnt/tmpfs/.aufs.xino unionfs /pup_new
+   [ $? -eq 0 ] || fatal_error "${L_ERROR_FAILED_AUFS_STACK}"
+  fi
+  if [ "$ONE_PREP" ];then
+   echo "mount -o remount,add:1:$ONE_LAYER /pup_new" #debug
+   mount -o remount,add:1:$ONE_LAYER /pup_new
+   [ $? -eq 0 ] || return 5
+  else
+   echo "mount -o remount,append:$ONE_LAYER /pup_new" #debug
+   mount -o remount,append:$ONE_LAYER /pup_new
+   [ $? -eq 0 ] || return 5
+  fi
  fi
  NEWUNIONRECORD="${NEWUNIONRECORD}${ONE_BASENAME} "
  return 0
@@ -451,17 +476,36 @@ setup_psave(){ # setup savefile or savefolder
   /sbin/load_ext_file "$SAVE_FN" "$SAVE_MP" #reads $PFSCK
   if [ -f /tmp/savefile_loop ] ; then
     . /tmp/savefile_loop # $SAVEFILE_LOOP $SFFS
-    [ -d "$SAVE_LAYER" ] || mkdir $SAVE_LAYER
-    echo "mount -t $SFFS -o noatime $SAVEFILE_LOOP $SAVE_LAYER" #debug
-    mount -t $SFFS -o noatime $SAVEFILE_LOOP $SAVE_LAYER
-    [ $? -ne 0 ] && PUPSAVE=""
+    if [ "$UNIONFS" = 'overlay' ]; then
+      mkdir /pup_loop
+      echo "mount -t $SFFS -o noatime $SAVEFILE_LOOP /pup_loop" #debug
+      mount -t $SFFS -o noatime $SAVEFILE_LOOP /pup_loop
+      if [ $? -ne 0 ]; then
+        PUPSAVE=""
+      else
+        mkdir -p "/pup_loop/upper" "/pup_loop/work"
+        ln -sv "/pup_loop/upper" "$SAVE_LAYER"
+        ln -sv "/pup_loop/work" "$WORKDIR"
+      fi
+    else
+      [ -d "$SAVE_LAYER" ] || mkdir $SAVE_LAYER
+      echo "mount -t $SFFS -o noatime $SAVEFILE_LOOP $SAVE_LAYER" #debug
+      mount -t $SFFS -o noatime $SAVEFILE_LOOP $SAVE_LAYER
+      [ $? -ne 0 ] && PUPSAVE=""
+    fi
   else # load_ext_file failed
     FLAG_NO_TIMEOUT=1
     PUPSAVE=""
   fi
  elif [ -d "$SAVE_FN" ];then #savefolder
   echo "--SAVEFOLDER-- $SAVE_FN" #debug
-  ln -sv "$SAVE_FN" "$SAVE_LAYER"
+  if [ "$UNIONFS" = 'overlay' ]; then
+   mkdir -p "$SAVE_FN/upper" "$SAVE_FN/work"
+   ln -sv "$SAVE_FN/upper" "$SAVE_LAYER"
+   ln -sv "$SAVE_FN/work" "$WORKDIR"
+  else
+   ln -sv "$SAVE_FN" "$SAVE_LAYER"
+  fi
  else
   PUPSAVE=""
  fi
@@ -662,7 +706,7 @@ $TRY_PARTS_LAST"
     fi
    fi
    if [ "$LOOK_PUP" ];then
-    find_drv_file "$P_BP_FN" "$P_DEF_FN"
+    find_drv_file "$P_BP_FN" "$P_DEF_FN" ""
     if [ "$ONE_FN" ];then
      PDRV="$ONE_PART,$ONE_FS,$ONE_FN"
      P_MP="$ONE_MP"
@@ -742,6 +786,25 @@ fatal_error() {
  check_status -critical 1 "$1"
 }
 
+remount_overlay() {
+ OPTS=`grep '^unionfs /pup_new overlay' /proc/mounts | awk '{print $4}'`
+ if [ -n "$OPTS" ]; then
+  umount -l /pup_new
+ else
+  mkdir /mnt/tmpfs/pup_work
+  OPTS="lowerdir=,upperdir=/mnt/tmpfs/pup_rw,workdir=/mnt/tmpfs/pup_work,xino=on"
+ fi
+ NEWOPTS=`echo "$OPTS" | sed -E "$@"`
+ echo "mount -t overlay -o ${NEWOPTS} unionfs /pup_new" #debug
+ mount -t overlay -o ${NEWOPTS} unionfs /pup_new
+ STATUS=$?
+ if [ $STATUS -ne 0 ]; then
+  echo "mount -t overlay -o ${OPTS} unionfs /pup_new" #debug
+  mount -t overlay -o ${OPTS} unionfs /pup_new
+ fi
+ return $STATUS
+}
+
 #=============================================================
 #                           MAIN
 #=============================================================
@@ -874,7 +937,7 @@ P_PART=""; LOOK_PUP=""; LOOK_SAVE=""
 if [ "$P_BP_ID" ];then #specified as parameter
  decode_id "$P_BP_ID"
  [ "$ONE_PART" ] && { P_PART="$ONE_PART"; P_BP_ID=""; }
- find_onepupdrv "$P_PART" "$P_BP_FN" "$P_DEF_FN" "p"
+ find_onepupdrv "$P_PART" "$P_BP_FN" "$P_DEF_FN" "p" ""
  [ "$ONE_FN" ] && { PDRV="$ONE_PART,$ONE_FS,$ONE_FN"; P_MP="$ONE_MP"; }
  [ "$PDEBUG" ] && echo "2: ONE_PART=$ONE_PART ONE_FN=$ONE_FN ONE_MP=$ONE_MP"
 elif [ "$PDRV" = "" ];then #not specified anywhere
@@ -931,8 +994,6 @@ RAMSIZE=$(free | grep -o 'Mem: .*' | tr -s ' ' | cut -f 2 -d ' ') #total physica
 
 mount -t tmpfs tmpfs /mnt/tmpfs
 [ -d "/mnt/tmpfs/pup_rw" ] || mkdir /mnt/tmpfs/pup_rw
-mount -t aufs -o udba=reval,diropq=w,br=/mnt/tmpfs/pup_rw=rw,xino=/mnt/tmpfs/.aufs.xino unionfs /pup_new 
-[ $? -eq 0 ] || fatal_error "${L_ERROR_FAILED_AUFS_STACK}"
 
 NEWUNIONRECORD=""
 COPY2RAM=""
@@ -961,27 +1022,27 @@ PUP_LAYER="$SFS_MP"
 [ "$SAVE_BP_ID" ] && log_part_id "$SAVE_BP_ID"
 
 #have basic system, now try to add optional stuff
-find_onepupdrv "$F_PART" "$F_BP_FN" "$F_DEF_FN" "f"
+find_onepupdrv "$F_PART" "$F_BP_FN" "$F_DEF_FN" "f" ""
 [ "$ONE_FN" ] && FDRV="$ONE_PART,$ONE_FS,$ONE_FN"
 [ "$FDRV" ] && { LOADMSG="fdrv"; setup_onepupdrv "$FDRV" "f"; }
 
-find_onepupdrv "$Z_PART" "$Z_BP_FN" "$Z_DEF_FN" "z"
+find_onepupdrv "$Z_PART" "$Z_BP_FN" "$Z_DEF_FN" "z" ""
 [ "$ONE_FN" ] && ZDRV="$ONE_PART,$ONE_FS,$ONE_FN"
 [ "$ZDRV" ] && { LOADMSG="zdrv"; setup_onepupdrv "$ZDRV" "z"; }
 
-find_onepupdrv "$Y_PART" "$Y_BP_FN" "$Y_DEF_FN" "y"
+find_onepupdrv "$Y_PART" "$Y_BP_FN" "$Y_DEF_FN" "y" ""
 [ "$ONE_FN" ] && YDRV="$ONE_PART,$ONE_FS,$ONE_FN"
 [ "$YDRV" ] && { LOADMSG="ydrv"; setup_onepupdrv "$YDRV" "y" "p"; }
 
-find_onepupdrv "$B_PART" "$B_BP_FN" "$B_DEF_FN" "b"
+find_onepupdrv "$B_PART" "$B_BP_FN" "$B_DEF_FN" "b" ""
 [ "$ONE_FN" ] && BDRV="$ONE_PART,$ONE_FS,$ONE_FN"
 [ "$BDRV" ] && { LOADMSG="bdrv"; setup_onepupdrv "$BDRV" "b" "p"; }
 
-find_onepupdrv "$A_PART" "$A_BP_FN" "$A_DEF_FN" "a"
+find_onepupdrv "$A_PART" "$A_BP_FN" "$A_DEF_FN" "a" ""
 [ "$ONE_FN" ] && ADRV="$ONE_PART,$ONE_FS,$ONE_FN"
 [ "$ADRV" ] && { LOADMSG="adrv"; setup_onepupdrv "$ADRV" "a" "p"; }
 
-find_onepupdrv "" "" "$KBUILD_DEF_FN" "k"
+find_onepupdrv "" "" "$KBUILD_DEF_FN" "k" ""
 [ "$ONE_FN" ] && KBUILD="$ONE_PART,$ONE_FS,$ONE_FN"
 [ "$KBUILD" ] && { LOADMSG="kbuild"; setup_onepupdrv "$KBUILD" "k" "p"; }
 
@@ -1152,6 +1213,7 @@ if [ "${SAVE_MP}" != "" -a "$PRAMONLY" != "yes" ];then #have mounted save? parti
 fi
 
 SAVE_LAYER=""
+WORKDIR="/pup_work"
 if [ "$PUPSAVE" ];then #refine pupmode
  # refine pupmode
  if [ $PUPMODE -eq 12 ];then
@@ -1179,8 +1241,14 @@ case $PUPMODE in
     #prepend ro1 - #SAVE_LAYER=/pup_ro1
     rm -rf ${SAVE_LAYER}/tmp #in case last boot was pupmode=12
     #adjust stack
-    echo "mount -o remount,add:1:${SAVE_LAYER}=ro+wh /pup_new" #debug
-    mount -o remount,add:1:${SAVE_LAYER}=ro+wh /pup_new #ro+wh = Readonly branch and it has/might have whiteouts on it
+    if [ "$UNIONFS" = 'overlay' ]; then
+     #pup_rw is bigger because files are copied, not moved to pup_ro1
+     mount -o remount,size=75% /mnt/tmpfs
+     remount_overlay "s~lowerdir=([^,]+)~lowerdir=${SAVE_LAYER}:\1~"
+    else
+     echo "mount -o remount,add:1:${SAVE_LAYER}=ro+wh /pup_new" #debug
+     mount -o remount,add:1:${SAVE_LAYER}=ro+wh /pup_new #ro+wh = Readonly branch and it has/might have whiteouts on it
+    fi
     if [ $? -eq 0 ];then
       [ $PUPMODE -ne 77 ] && KEEPMOUNTED="${KEEPMOUNTED}${SAVEPART} "
       [ "$SAVE_NAME" ] && NEWUNIONRECORD="$SAVE_NAME $NEWUNIONRECORD"
@@ -1196,8 +1264,12 @@ case $PUPMODE in
     #setup empty /tmp on tmpfs for in stack
     rm -rf ${SAVE_LAYER}/tmp
     #adjust stack
-    echo "mount -o remount,prepend:${SAVE_LAYER}=rw,mod:/mnt/tmpfs/pup_rw=ro,del:/mnt/tmpfs/pup_rw /pup_new" #debug
-    mount -o remount,prepend:${SAVE_LAYER}=rw,mod:/mnt/tmpfs/pup_rw=ro,del:/mnt/tmpfs/pup_rw /pup_new
+    if [ "$UNIONFS" = 'overlay' ]; then
+     remount_overlay -e "s~upperdir=[^,]+~upperdir=${SAVE_LAYER}~" -e "s~workdir=[^,]+~workdir=${WORKDIR}~"
+    else
+     echo "mount -o remount,prepend:${SAVE_LAYER}=rw,mod:/mnt/tmpfs/pup_rw=ro,del:/mnt/tmpfs/pup_rw /pup_new" #debug
+     mount -o remount,prepend:${SAVE_LAYER}=rw,mod:/mnt/tmpfs/pup_rw=ro,del:/mnt/tmpfs/pup_rw /pup_new
+    fi
     if [ $? -eq 0 ];then
       rm -rf /mnt/tmpfs/pup_rw
       KEEPMOUNTED="${KEEPMOUNTED}${SAVEPART} "
@@ -1216,13 +1288,23 @@ case $PUPMODE in
     rm -r -f "$PM66_DIR"
     [ -d "$PM66_DIR" ] || mkdir $PM66_DIR
     mount -t tmpfs tmpfs $PM66_DIR
-    tar xf "$ARCHIVE_FN" -m -C $PM66_DIR 2>/dev/null
-    STATUS=$?
-    if [ $STATUS -eq 0 ];then
-      #replace rw branch with new populated tmpfs
-      echo "mount -o remount,prepend:${PM66_DIR}=rw,mod:/mnt/tmpfs/pup_rw=ro,del:/mnt/tmpfs/pup_rw /pup_new" #debug
-      mount -o remount,prepend:${PM66_DIR}=rw,mod:/mnt/tmpfs/pup_rw=ro,del:/mnt/tmpfs/pup_rw /pup_new
+    if [ "$UNIONFS" = 'overlay' ]; then
+      mkdir $PM66_DIR/upper $PM66_DIR/work
+      tar xf "$ARCHIVE_FN" -m -C $PM66_DIR/upper 2>/dev/null
+      STATUS=$?
+      if [ $STATUS -eq 0 ];then
+        remount_overlay -e "s~upperdir=[^,]+~upperdir=${PM66_DIR}/upper~" -e "s~workdir=[^,]+~workdir=${PM66_DIR}/work~"
+        STATUS=$?
+      fi
+    else
+      tar xf "$ARCHIVE_FN" -m -C $PM66_DIR 2>/dev/null
       STATUS=$?
+      if [ $STATUS -eq 0 ];then
+        #replace rw branch with new populated tmpfs
+        echo "mount -o remount,prepend:${PM66_DIR}=rw,mod:/mnt/tmpfs/pup_rw=ro,del:/mnt/tmpfs/pup_rw /pup_new" #debug
+        mount -o remount,prepend:${PM66_DIR}=rw,mod:/mnt/tmpfs/pup_rw=ro,del:/mnt/tmpfs/pup_rw /pup_new
+        STATUS=$?
+      fi
     fi
     if [ $STATUS -eq 0 ];then
       SAVE_MP=''
@@ -1238,6 +1320,16 @@ case $PUPMODE in
  ;;
 esac
 
+if [ "$SAVEPART" -a "$UNIONFS" = 'overlay' -a -f /pup_new/etc/rc.d/BOOTCONFIG ]; then
+ EXTRASFSLIST=""
+ . /pup_new/etc/rc.d/BOOTCONFIG
+ for ONE_SFS in $EXTRASFSLIST; do
+  LOOP=`losetup -f`
+  find_onepupdrv "$SAVEPART" "" "$ONE_SFS" "p" "1"
+  [ "$ONE_FN" ] && { LOADMSG="extra"; setup_onepupdrv "$ONE_PART,$ONE_FS,$ONE_FN" "ro${LOOP#/dev/loop}" "p"; }
+ done
+fi
+
 umount_unneeded
 
 echo -n $(($TOTAL_SIZEK_SFS_RAM - 5)) > /tmp/sfs_ram_sizek
@@ -1275,7 +1367,7 @@ echo "PSAVEMARK='$PSAVEMARK'"
 echo "PSAVEPART='$PSAVEPART'"
 echo "PSAVEDIR='$SAVE_BP_DIR'"
 echo "PSUBDIR='$PSUBDIR'"
-echo "PUNIONFS='aufs'"
+echo "PUNIONFS='$UNIONFS'"
 echo "DOIMODS='yes'"
 echo "DOMIBS='no'"
 [ -f /sbin/set_plang ] && plang_pupstate #echo
@@ -1290,19 +1382,21 @@ else
  echo "LASTUNIONRECORD=''" >> /pup_new/etc/rc.d/BOOTCONFIG
 fi
 
-echo -n "${L_SWITCH_ROOT}" > /dev/console
+echo -n "$(printf "${L_SWITCH_ROOT}" "${UNIONFS}")" >/dev/console
 
 echo "Moving mountpoints to /pup_new/initrd for after switch..." #debug
 rm -r -f "/pup_new/initrd${SAVE_LAYER}"
+OPT="move"
+[ "$UNIONFS" = 'overlay' ] && OPT="bind"
 for ONEMNT in $(mount | cut -f 3 -d ' ' | grep -v 'pup_new' | grep '^/pup_' | tr '\n' ' ');do
  mkdir -p /pup_new/initrd${ONEMNT}
- echo "mount -o move $ONEMNT /pup_new/initrd${ONEMNT}" #debug
- mount -o move $ONEMNT /pup_new/initrd${ONEMNT}
+ echo "mount -o $OPT $ONEMNT /pup_new/initrd${ONEMNT}" #debug
+ mount -o $OPT $ONEMNT /pup_new/initrd${ONEMNT}
 done
 for ONEMNT in $(mount | cut -f 3 -d ' ' | grep '^/mnt/' | tr '\n' ' ');do
  mkdir -p /pup_new/initrd${ONEMNT}
- echo "mount -o move $ONEMNT /pup_new/initrd${ONEMNT}" #debug
- mount -o move $ONEMNT /pup_new/initrd${ONEMNT}
+ echo "mount -o $OPT $ONEMNT /pup_new/initrd${ONEMNT}" #debug
+ mount -o $OPT $ONEMNT /pup_new/initrd${ONEMNT}
 done
 
 echo -------------------- # debug
@@ -1324,7 +1418,7 @@ echo "SAVE_LAYER=${SAVE_LAYER}" #debug
 # (for savefiles and savepartitions the SAVE_LAYER is not a symlink)
 if [ "$PUPSAVE" ];then
  if [ "$SAVE_LAYER" -a -L "$SAVE_LAYER" ];then
-  ln -sv "/initrd${SAVE_FN}" "/pup_new/initrd${SAVE_LAYER}" #for after switch
+  ln -sv "/initrd`readlink ${SAVE_LAYER}`" "/pup_new/initrd${SAVE_LAYER}" #for after switch
  fi
 fi
 
diff --git a/woof-code/3builddistro b/woof-code/3builddistro
index 77a0fd31bd9..5c36407358c 100755
--- a/woof-code/3builddistro
+++ b/woof-code/3builddistro
@@ -886,6 +886,8 @@ if [ "$SDFLAG" != "" -o "$CROSFLAG" != "" ];then
 	echo "BOOT_BOARD='${BOOT_BOARD}'" >> rootfs-complete/etc/rc.d/BOOTCONSTRAINED #120714 read by quicksetup.
 fi
 
+echo "PUNIONFS='$UNIONFS'" >> rootfs-complete/etc/rc.d/PUPSTATE
+
 # users shouldn't be able to read files under another home directory - i.e. leak .netrc
 busybox chmod 700 rootfs-complete/root rootfs-complete/home/spot
 
diff --git a/woof-code/rootfs-skeleton/etc/rc.d/rc.shutdown b/woof-code/rootfs-skeleton/etc/rc.d/rc.shutdown
index b42c4c213ca..67f94eecbab 100755
--- a/woof-code/rootfs-skeleton/etc/rc.d/rc.shutdown
+++ b/woof-code/rootfs-skeleton/etc/rc.d/rc.shutdown
@@ -265,23 +265,31 @@ case $PUPMODE in
    mount -t $FILEFS -o noatime,rw /dev/mapper/savefile /tmp/save1stpup
   fi
   #120522 testing precise puppy with aufs, have two dirs here .wh..wh.orph, .wh..wh.plnk, filter out...
-  RDIRS="`find /initrd/pup_rw/ -mindepth 1 -maxdepth 1 -mount -type d | grep -v '/\.wh\.' | grep -v -E '/$|/mnt|/media|/tmp|/proc|/sys|/dev|/lost' | tr '\n' ' '`"
+  if [ "$PUNIONFS" = 'overlay' ]; then
+   mkdir -p /tmp/save1stpup/upper
+   PFIX="/upper"
+   RDIRS="`find /initrd/pup_rw/ -mindepth 1 -maxdepth 1 -mount -type d | grep -v -E '/$|^/initrd/pup_rw/initrd|/mnt|/media|/tmp|/proc|/sys|/dev|/lost' | tr '\n' ' '`"
+  else
+   PFIX=""
+   RDIRS="`find /initrd/pup_rw/ -mindepth 1 -maxdepth 1 -mount -type d | grep -v '/\.wh\.' | grep -v -E '/$|/mnt|/media|/tmp|/proc|/sys|/dev|/lost' | tr '\n' ' '`"
+  fi
   for ONEDIR in $RDIRS
   do
    BASENAME="`basename $ONEDIR`"
    # set owner/permission of dirs when 1st save. this is important when choose to run as finn on 1st shutdown.
-   if [ ! -d /tmp/save1stpup/${BASENAME} ];then
-    mkdir -p /tmp/save1stpup/${BASENAME}
+   if [ ! -d /tmp/save1stpup${PFIX}/${BASENAME} ];then
+    mkdir -p /tmp/save1stpup${PFIX}/${BASENAME}
     #110503 got this from /usr/sbin/snapmergepuppy...
-    chmod "/tmp/save1stpup/${BASENAME}" --reference="$ONEDIR"
+    chmod "/tmp/save1stpup${PFIX}/${BASENAME}" --reference="$ONEDIR"
     OWNER="`stat -c %U "$ONEDIR"`"
-    chown $OWNER "/tmp/save1stpup/${BASENAME}"
+    chown $OWNER "/tmp/save1stpup${PFIX}/${BASENAME}"
     GRP="`stat -c %G "$ONEDIR"`"
-    chgrp $GRP "/tmp/save1stpup/${BASENAME}"
-    touch "/tmp/save1stpup/${BASENAME}" --reference="$ONEDIR"
+    chgrp $GRP "/tmp/save1stpup${PFIX}/${BASENAME}"
+    touch "/tmp/save1stpup${PFIX}/${BASENAME}" --reference="$ONEDIR"
    fi
-   cp -a $ONEDIR/ /tmp/save1stpup/
+   cp -a $ONEDIR/ /tmp/save1stpup${PFIX}/
   done
+  [ "$PUNIONFS" = 'overlay' ] && find /tmp/save1stpup${PFIX} -type c -delete
   #copy initmodules config file from /tmp if it exists
   [ -f /tmp/${DISTRO_FILE_PREFIX}initmodules.txt ] && cp -f /tmp/${DISTRO_FILE_PREFIX}initmodules.txt ${SMNTPT}${SAVEPATH}/${DISTRO_FILE_PREFIX}initmodules.txt
   sync
@@ -410,7 +418,7 @@ if [ "$SAVE_LAYER" ];then
 		   #remove from unionfs
 		   if [ "$uniFS" == "aufs" ]; then
 		    busybox mount -t aufs -o remount,del:/initrd${SAVE_LAYER} unionfs /
-		   else
+		   elif [ "$uniFS" != "overlay" ]; then
 		    busybox mount -t unionfs -o remount,del=/initrd${SAVE_LAYER} unionfs /
 		   fi
 		
@@ -436,7 +444,7 @@ if [ "$SAVE_LAYER" ];then
 	    #Remove from unionfs
 	    if [ "$uniFS" == "aufs" ]; then
 	     busybox mount -t aufs -o remount,del:${PDRVPATH} unionfs /
-	    else
+	    elif [ "$uniFS" != "overlay" ]; then
 	     busybox mount -t unionfs -o remount,del=${PDRVPATH} unionfs /
 	    fi
 
diff --git a/woof-code/rootfs-skeleton/etc/rc.d/rc.sysinit b/woof-code/rootfs-skeleton/etc/rc.d/rc.sysinit
index ec217962130..e2a1e06721f 100755
--- a/woof-code/rootfs-skeleton/etc/rc.d/rc.sysinit
+++ b/woof-code/rootfs-skeleton/etc/rc.d/rc.sysinit
@@ -285,7 +285,11 @@ if [ "$SWAPON" = "yes" ];then
  # taking into account swap space and sfs_ram_sizek[might be removed]
  EXTRAALLOCK=$(($EXTRAALLOCK / 2048)) #use half in KiB
  RAMSIZE=$(free | grep -o 'Mem: .*' | tr -s ' ' | cut -f 2 -d ' ')
- FREEK=$(($RAMSIZE / 2)) #half of physical.
+ if [ "$PUNIONFS" = "overlay" -a $PUPMODE -eq 13 ]; then
+  FREEK=$(($RAMSIZE * 3 / 4)) #3/4 of physical.
+ else
+  FREEK=$(($RAMSIZE / 2)) #half of physical.
+ fi
  ALLOCK=$(($FREEK + $EXTRAALLOCK))
  if [ "$(grep -m 1 '/initrd/mnt/tmpfs' /proc/mounts)" != "" ];then #mounted
   [ -s /initrd/tmp/sfs_ram_sizek ] && ALLOCK=$(($ALLOCK + $(cat /initrd/tmp/sfs_ram_sizek))) #proper size
diff --git a/woof-code/rootfs-skeleton/etc/rc.d/rc.update b/woof-code/rootfs-skeleton/etc/rc.d/rc.update
index b95ba6c30ba..f886bd6920d 100755
--- a/woof-code/rootfs-skeleton/etc/rc.d/rc.update
+++ b/woof-code/rootfs-skeleton/etc/rc.d/rc.update
@@ -298,7 +298,7 @@ if [ -f /initrd/tmp/version_update_flag ]; then
  for ONESCRIPT in dir2pet dirs2pets evince gtkdialog-splash lprshell man new2dir pet2tgz petspec pman pupdialog restartwm startx tgz2pet wmexit wmpoweroff wmreboot wvdialshell xterm xwin yaf-splash
  do [ -f ${OLDFILESMNTPT}/bin/$ONESCRIPT ] && cp -a -f --remove-destination ${NEWFILESMNTPT}/usr/bin/$ONESCRIPT /usr/bin/ 2>/dev/null
  done
- for ONESCRIPT in alsawizard askpass background_reshape bcrypt_gui bootflash bootmanager burniso2cd calcfreespace.sh cdburner-wizard chooselocale connectwizard connectwizard_2nd countrywizard cups_shell dotpup delayedrun deskshortcut.sh download_file eventmanager exploderpm filemnt fitimage2root fixdesk fixmenus fixPuppyPin floppy-format.sh freememappletshell gen_modem_init_string get_bluetooth_connection get_modem_alternate_device grubconfig grubconfigREADME.txt icon_switcher icon_switcher_cli input-wizard ipinfo loginmanager modemdisconnect modemprobe modemprobe_erase modemprobe_help modemtest networkdisconnect partview pcur pdict Pdisk petget pgprs-shell pmodemdiag pmonitork.sh pmonitorx.sh pmount pmovie pngoverlay pngoverlay.bac pngoverlay.sh pppconnect pppdisconnect pppsetup Pudd pup-advert-blocker pupautodetect pupcamera pupdial pupdial_init_hotpluggable pupdial_wizard_helper puppyhelp puppyinstaller puppypdf pupscan remasterpup2 remove_builtin report-video resizepfile.sh root2user save2flash savesession-dvd scannerwizard.sh securetelnetshell set_bg set_hwclock_type set-time-for-puppy set-xftdpi sfsget shutdownconfig snapmergepuppy sns spacereplace timezone-set updatenetmoduleslist.sh usb_modem_special_status usb_modeswitch_status video_upgrade_wizard video-wizard welcome1stboot welcome1stboot.bac wizardwizard xdelta_gui xgamma-gui xinitrc_test xorgwizard xorgwizard-automatic xrandrshell xserverwizard
+ for ONESCRIPT in alsawizard askpass background_reshape bcrypt_gui bootflash bootmanager burniso2cd calcfreespace.sh cdburner-wizard chooselocale connectwizard connectwizard_2nd countrywizard cups_shell dotpup delayedrun deskshortcut.sh download_file eventmanager exploderpm filemnt fitimage2root fixdesk fixmenus fixPuppyPin floppy-format.sh freememappletshell gen_modem_init_string get_bluetooth_connection get_modem_alternate_device grubconfig grubconfigREADME.txt icon_switcher icon_switcher_cli input-wizard ipinfo loginmanager modemdisconnect modemprobe modemprobe_erase modemprobe_help modemtest networkdisconnect partview pcur pdict Pdisk petget pgprs-shell pmodemdiag pmonitork.sh pmonitorx.sh pmount pmovie pngoverlay pngoverlay.bac pngoverlay.sh pppconnect pppdisconnect pppsetup Pudd pup-advert-blocker pupautodetect pupcamera pupdial pupdial_init_hotpluggable pupdial_wizard_helper puppyhelp puppyinstaller puppypdf pupscan remasterpup2 remove_builtin report-video resizepfile.sh root2user save2flash savesession-dvd scannerwizard.sh securetelnetshell set_bg set_hwclock_type set-time-for-puppy set-xftdpi sfsget shutdownconfig snapmergepuppy snapmergepuppy.overlay sns spacereplace timezone-set updatenetmoduleslist.sh usb_modem_special_status usb_modeswitch_status video_upgrade_wizard video-wizard welcome1stboot welcome1stboot.bac wizardwizard xdelta_gui xgamma-gui xinitrc_test xorgwizard xorgwizard-automatic xrandrshell xserverwizard
  do [ -f ${OLDFILESMNTPT}/bin/$ONESCRIPT ] && cp -a -f --remove-destination ${NEWFILESMNTPT}/usr/sbin/$ONESCRIPT /usr/sbin/ 2>/dev/null
  done
  [ -f ${OLDFILESMNTPT}usr/local/petget ] && cp -a -f --remove-destination ${NEWFILESMNTPT}/usr/local/petget /usr/local/ 
diff --git a/woof-code/rootfs-skeleton/usr/sbin/resizepfile.sh b/woof-code/rootfs-skeleton/usr/sbin/resizepfile.sh
index d3d798fef4e..f71c4d57b8c 100755
--- a/woof-code/rootfs-skeleton/usr/sbin/resizepfile.sh
+++ b/woof-code/rootfs-skeleton/usr/sbin/resizepfile.sh
@@ -23,6 +23,11 @@ $(eval_gettext "If you have installed Puppy to hard drive, or installed such tha
 
 esac
 
+if [ -L "$PERSISTMNTPT" ] ; then
+	PERSISTMNTPT="`readlink "$PERSISTMNTPT"`"
+	[ -d "$PERSISTMNTPT" ] && PERSISTMNTPT="${PERSISTMNTPT%/upper}"
+fi
+
 SAVEFS="`echo -n "$PUPSAVE" | cut -f 2 -d ','`"
 SAVEPART="`echo -n "$PUPSAVE" | cut -f 1 -d ','`"
 SAVEFILE="`echo -n "$PUPSAVE" | cut -f 3 -d ','`"
diff --git a/woof-code/rootfs-skeleton/usr/sbin/sfs_load b/woof-code/rootfs-skeleton/usr/sbin/sfs_load
index 49f039c8641..5fde9ce7d7d 100755
--- a/woof-code/rootfs-skeleton/usr/sbin/sfs_load
+++ b/woof-code/rootfs-skeleton/usr/sbin/sfs_load
@@ -84,7 +84,7 @@ fi
 
 
 if [ "$PUNIONFS" = "overlay" ] ; then
-	exit
+	exec sfs_load.overlay "$@"
 fi
 
 for i in $@ ; do
diff --git a/woof-code/rootfs-skeleton/usr/sbin/sfs_load.overlay b/woof-code/rootfs-skeleton/usr/sbin/sfs_load.overlay
new file mode 100755
index 00000000000..14e8ee77da1
--- /dev/null
+++ b/woof-code/rootfs-skeleton/usr/sbin/sfs_load.overlay
@@ -0,0 +1,118 @@
+#!/bin/sh
+
+. /etc/rc.d/BOOTCONFIG
+. /etc/rc.d/PUPSTATE
+. /etc/DISTRO_SPECS
+
+[ "$PUNIONFS" != "overlay" ] && exit 1
+
+export TEXTDOMAIN=sfs_load
+export OUTPUT_CHARSET=UTF-8
+
+queue() {
+	. /etc/rc.d/BOOTCONFIG
+	cat << EOF > /etc/rc.d/BOOTCONFIG.tmp
+EXTRASFSLIST='`echo "$EXTRASFSLIST $1" | tr ' ' '\n' | sort | uniq | tr '\n' ' ' | sed -e 's/^ //' -e 's/ $//'`'
+PREVUNIONRECORD='$PREVUNIONRECORD'
+LASTUNIONRECORD='$LASTUNIONRECORD'
+EOF
+	mv -f /etc/rc.d/BOOTCONFIG.tmp /etc/rc.d/BOOTCONFIG
+}
+
+unqueue() {
+	. /etc/rc.d/BOOTCONFIG
+	cat << EOF > /etc/rc.d/BOOTCONFIG.tmp
+EXTRASFSLIST='`echo "$EXTRASFSLIST $1" | tr ' ' '\n' | sort | uniq | fgrep -v $1 | tr '\n' ' ' | sed -e 's/^ //' -e 's/ $//'`'
+PREVUNIONRECORD='$PREVUNIONRECORD'
+LASTUNIONRECORD='$LASTUNIONRECORD'
+EOF
+	mv -f /etc/rc.d/BOOTCONFIG.tmp /etc/rc.d/BOOTCONFIG
+}
+
+if [ $# -ne 0 ]; then
+	for SFS in "$@"; do
+		BASE="${SFS##*/}"
+
+		SKIP=0
+		case "$BASE" in
+		$DISTRO_BDRVSFS|$DISTRO_PUPPYSFS|$DISTRO_ZDRVSFS|$DISTRO_FDRVSFS|$DISTRO_ADRVSFS|$DISTRO_YDRVSFS|kbuild-*.sfs) SKIP=1 ;;
+		esac
+
+		if [ $SKIP -eq 0 -a $PUPMODE -ne 5 ]; then
+			QUEUED=0
+			for QBASE in $EXTRASFSLIST; do
+				[ "$BASE" != "$QBASE" ] && continue
+				QUEUED=1
+				break
+			done
+
+			if [ $QUEUED -eq 0 ]; then
+				yad --title sfs_load --window-icon=dialog-question --image=dialog-question --text "$(gettext "Do you want to queue") ${SFS}?" --form --button="gtk-yes:0" --button="gtk-no:1"
+				if [ $? -eq 0 ]; then
+					DST="/initrd${PUP_HOME}${PSUBDIR}/${BASE}"
+					if [ ! -e "$DST" -a ! -e "/initrd${PUP_HOME}/${BASE}" ]; then
+						cp -f "$SFS" "$DST" || continue
+					fi
+					SFS="$DST"
+					queue "$BASE"
+				fi
+			else
+				yad --title sfs_load --window-icon=dialog-question --image=dialog-question --text "$(gettext "Do you want to unqueue") ${SFS}?" --form --button="gtk-yes:0" --button="gtk-no:1"
+				[ $? -eq 0 ] && unqueue "$BASE"
+			fi
+		fi
+
+		MNT="/mnt/`echo "$BASE" | tr '/ ' '+_'`"
+		mkdir -p "$MNT"
+		mountpoint -q "$MNT"
+		if [ $? -ne 0 ]; then
+			mount -r -t squashfs -o loop,noatime "$SFS" "$MNT" || continue
+		fi
+
+		defaultfilemanager "$MNT" &
+	done
+
+	exit 0
+fi
+
+export -f queue unqueue
+
+if [ -z "$PUP_HOME" ]; then
+	SFS_DIRS="/initrd/mnt/pdrv"
+else
+	SFS_DIRS="/initrd${PUP_HOME}"
+	[ -n "$PSUBDIR" ] && SFS_DIRS="$SFS_DIRS /initrd${PUP_HOME}${PSUBDIR}"
+fi
+
+BUTTONS=""
+KBUILDSFS="kbuild-`uname -r`.sfs"
+for SFS in `find $SFS_DIRS -maxdepth 1 -name '*.sfs' -printf '%f\n' | sort | uniq`; do
+	case "$SFS" in
+	$DISTRO_BDRVSFS|$DISTRO_PUPPYSFS|$DISTRO_ZDRVSFS|$DISTRO_FDRVSFS|$DISTRO_ADRVSFS|$DISTRO_YDRVSFS|$KBUILDSFS)
+		BUTTONS="<togglebutton><label>$SFS</label><default>true</default><sensitive>false</sensitive></togglebutton>$BUTTONS"
+		continue
+		;;
+	esac
+
+	DEF=false
+	for BASE in $EXTRASFSLIST; do
+		[ "$BASE" != "$SFS" ] && continue
+		DEF=true
+		break
+	done
+
+	BUTTONS="$BUTTONS<togglebutton><label>$SFS</label><default>$DEF</default><action>if true queue \"$SFS\"</action><action>if false unqueue \"$SFS\"</action></togglebutton>"
+done
+
+[ -z "$BUTTONS" ] && BUTTONS="<text><label>$(gettext 'Could not find any SFS to queue.')</label></text>"
+
+export DIALOG='<window title="SFS-Load" default_width="400">
+	<vbox space-expand="true" space-fill="true">
+		'`/usr/lib/gtkdialog/xml_info fixed package_sfs.svg 20 "$(gettext "Which SFS do you want to load?")"`'
+		<vbox scrollable="true" height="400">
+		'$BUTTONS'
+		</vbox>
+	</vbox>
+</window>'
+
+exec gtkdialog -p DIALOG
\ No newline at end of file
diff --git a/woof-code/rootfs-skeleton/usr/sbin/snapmergepuppy b/woof-code/rootfs-skeleton/usr/sbin/snapmergepuppy
index 10aa2b07586..61ec4a06348 100755
--- a/woof-code/rootfs-skeleton/usr/sbin/snapmergepuppy
+++ b/woof-code/rootfs-skeleton/usr/sbin/snapmergepuppy
@@ -28,6 +28,14 @@
 #140102 SFR: various fixes + gettext
 #140512 SFR: performance improvements
 
+#variables created at bootup by 'init' script in initramfs...
+. /etc/rc.d/PUPSTATE
+
+if [ "$PUNIONFS" = 'overlay' ]; then
+ snapmergepuppy.overlay "$@"
+ exit $?
+fi
+
 remove_merge_lock() {
  if [ $? -ne 255 ]; then
   [ -e /tmp/snapmergepuppy.lock ] && rm -f /tmp/snapmergepuppy.lock
@@ -46,8 +54,6 @@ export OUTPUT_CHARSET=UTF-8
 OLDLANG="$LANG"
 export LANG=C
 
-#variables created at bootup by 'init' script in initramfs...
-. /etc/rc.d/PUPSTATE
 . /etc/DISTRO_SPECS
 
 [ "`whoami`" != "root" ] && exec sudo -A ${0} ${@}
diff --git a/woof-code/rootfs-skeleton/usr/sbin/snapmergepuppy.overlay b/woof-code/rootfs-skeleton/usr/sbin/snapmergepuppy.overlay
new file mode 100755
index 00000000000..818b482c219
--- /dev/null
+++ b/woof-code/rootfs-skeleton/usr/sbin/snapmergepuppy.overlay
@@ -0,0 +1,227 @@
+#!/bin/sh
+#2007 Lesser GPL licence v2 (http://www.fsf.org/licensing/licenses/lgpl.html)
+#Barry Kauler www.puppylinux.com
+#called from savepuppyd and rc.shutdown, to save tmpfs layer to permanent flash storage.
+#updated 13 Sept 2007. copy-down only. flushing is done in petget.
+#updated 24 Sept 2007. removed '-u' option when copy-down files.
+#8 oct 2007: screen out /root/tmp when saving.
+#4 nov 2007: reintroduce '-u' copy option.
+#v4.01 19may2008 BK: now called from /sbin/pup_eventd daemon (savepuppyd now history).
+#v4.01 19may2008 BK: if called from pup_eventd then X running: graceful exit if X shutdown.
+#v409 BK: save /var dir. previously screened out to save space, but prevents crontab from running.
+#v412 /etc/DISTRO_SPECS, renamed pup_xxx.sfs, pup_save.2fs etc.
+#w000 pup files renamed to woofr555.sfs, woofsave.2fs.
+#w003 screened out some dirs in /dev that should not be saved.
+#v424 fix for more layers in unionfs/aufs.
+#100222 shinobar: possible timezone problem with BOOTCONFIG. more file exclusions.
+#100422 added ^root/ftpd exclusion.
+#100429 modify 'trash' exclusion.
+#100820 added /var/tmp exclusion (apparently filled by opera crashes).
+#101221 yaf-splash fix.
+#110206 Dougal: clean up some testing. speedup: LANG=C, also change to /bin/ash.
+#110212 Jemimah: files may disappear, more efficient calc of free space, fix i/o err.
+#110222 shinobar: remove all /dev, allow 'pup_ro10-19', exit code for no space
+#110224 BK: revert remove all /dev, for now. 110503 added dev/snd
+#110505 support sudo for non-root user.
+#111229 rerwin: fix jemimah code (110212).
+#120103 rerwin: screen out /.XLOADED when save.
+#140102 SFR: various fixes + gettext
+#140512 SFR: performance improvements
+
+remove_merge_lock() {
+ if [ $? -ne 255 ]; then
+  [ -e /tmp/snapmergepuppy.lock ] && rm -f /tmp/snapmergepuppy.lock
+ fi
+}
+
+trap remove_merge_lock EXIT
+trap remove_merge_lock SIGKILL
+trap remove_merge_lock SIGTERM
+
+[ -e /tmp/snapmergepuppy.lock ] && exit 255
+
+export TEXTDOMAIN=snapmergepuppy
+export OUTPUT_CHARSET=UTF-8
+
+OLDLANG="$LANG"
+export LANG=C
+
+#variables created at bootup by 'init' script in initramfs...
+. /etc/rc.d/PUPSTATE
+. /etc/DISTRO_SPECS
+
+[ "`whoami`" != "root" ] && exec sudo -A ${0} ${@}
+
+touch /tmp/snapmergepuppy.lock
+
+if [ $PUPMODE -ne 13 ] ; then
+	echo "$0: Wrong PUPMODE ($PUPMODE)"
+	exit 1
+fi
+
+SAVEPART="`echo -n "$PUPSAVE" | cut -f 1 -d ','`"
+
+SHUTDOWN="no"
+pidof rc.shutdown >/dev/null && SHUTDOWN="yes"
+XRUNNING="no"
+pidof X >/dev/null 2>&1 || pidof Xorg >/dev/null 2>&1 || pidof Xwayland >/dev/null 2>&1 && XRUNNING="yes"
+
+PATH="/bin:/sbin:/usr/bin:/usr/sbin:/usr/X11R7/bin"
+WD="`pwd`"
+
+ # all the action takes places inside $SNAP
+SNAP="/initrd/pup_rw"
+cd $SNAP || exit 1
+
+# files are copied from $SNAP/* to $BASE/
+BASE="/initrd/pup_ro1"
+BASEDEV="`grep -m1 /initrd/mnt/dev_save /proc/mounts | cut -f 1 -d ' '`"
+
+# Precautions
+[ "$BASEDEV" ] || { echo "$BASEDEV is not mounted!"; exit 1; }
+
+echo "Merging $SNAP onto $BASE..."
+
+# =============================================================================
+# WHITEOUTS
+# =============================================================================
+
+SFSPoints="`grep -m1 ^unionfs /proc/mounts | sed -E 's~.*lowerdir=([^,]+).*~\1~' | sed -e s~^~/initrd~ -e 's~:~\n/initrd~g' | grep -v '^/initrd/pup_ro1$' | tac`"
+
+find . -type c | sed -e 's/\.\///' |
+while read -r N
+do
+	DN="${N%/*}"
+	BN="${N##*/}"
+	[ "$DN" = "$N" ] || [ "$DN" = "" ] && DN="."
+	[ "$DN" = "." ] && continue
+
+	[ "`stat -c '%t,%T' "$N" 2>/dev/null`" != '0,0' ] && continue
+	if [ -c "$BASE/$N" ]; then
+		[ "`stat -c '%t,%T' "$BASE/$N"`" = '0,0' ] && continue
+	fi
+
+	rm -rf "$BASE/$N"
+ 
+	#if file exists on a lower layer, have to save the whiteout file...
+	#110206 Dougal: speedup and refine the search...
+	for P in $SFSPoints
+	do
+		if [ -e "$P/$N" ] || [ -L "$P/$N" ] ; then	# SFR: broken symlinks also deserve to be processed ( '-e' won't detect them, needs to be also '-L')
+			[ -d "${BASE}/${DN}" ] || mkdir -p "${BASE}/${DN}"
+			mknod "${BASE}/${N}" c 0 0
+			break
+		fi
+	done #110206 End Dougal.
+done
+
+# =============================================================================
+# DIRECTORIES
+# =============================================================================
+
+find . -mount -type d | tail +2 | sed -e 's/\.\///' | grep -v -E '^mnt|^media|^initrd|^proc|^sys|^tmp|^root/tmp|^dev|^var/tmp|^var/lock' |
+while read -r N
+do
+	#v4.01 graceful exit if shutdown X (see /usr/X11R7/bin/restartwm,wmreboot,wmpoweroff)...
+	[ "$XRUNNING" = "yes" ] && [ -f /tmp/wmexitmode.txt ] && exit
+	mkdir -p "$BASE/$N"
+	#i think nathan advised this, to handle non-root user (SFR: improved/simplified)
+	chmod "$BASE/$N" --reference="$N"
+	OWNERSHIP="`stat -c %u:%g "$N"`"
+	chown $OWNERSHIP "$BASE/$N"
+	touch "$BASE/$N" --reference="$N"
+done
+
+# =============================================================================
+# FILES
+# =============================================================================
+
+FREEBASE=`df -B 1 | grep -m1 "^$BASEDEV" | tr -s ' ' | cut -f 4 -d ' '` #110212 Jemimah #110222 shinobar # SFR: result in bytes (see 'find' below)
+
+rm -f /tmp/snapmergepuppy-nospace #110222 shinobar
+rm -f /tmp/snapmergepuppy-error   #140102 SFR
+
+#Copy Files... v409 remove '^var'. 100222 shinobar: more exclusions. 100422 added ^root/ftpd. 100429 modify 'trash' exclusion. 100820 added var/tmp 120103 rerwin: add .XLOADED # SFR: added dev/snd # SFR: added .crdownload
+# SFR: move as much as possible into 'find' itself
+# Limitation - files with newline (\n) in its name are processed wrong (but this is not a new issue)
+find . -mount \
+	   -not -path . \
+	   -not -type d \
+	   -not -type c \
+	   -regextype posix-extended \
+	   -not \( -regex '^./initrd.*|^./mnt.*|^./media.*|^./proc.*|^./sys.*|^./tmp.*|^./pup_.*|^./zdrv_.*|^./root/tmp.*|.*_zdrv_.*|^./dev.*|^./var/run.*|^./root/ftpd.*|^./var/tmp.*|^./var/lock.*|.*\.XLOADED$' \) \
+	   -not \( -regex '.*\.thumbnails.*|.*\.part$|.*\.crdownload$' \) \
+	   -printf "%C@ %s %P\n" | sort -rn |
+while read -r NCTIME NSIZE N
+do
+	#v4.01 graceful exit if shutdown X (see /usr/X11R7/bin/restartwm,wmreboot,wmpoweroff)...
+	[ "$XRUNNING" = "yes" ] && [ -f /tmp/wmexitmode.txt ] && exit
+
+	if [ ! -e "$N" ] && [ ! -L "$N" ] ; then
+		continue # SFR: skip non-existing files (btw, '-e' won't detect broken symlinks, so '-L' is necessary!)
+	fi
+
+	#stop saving if not enough room left in ${DISTRO_FILE_PREFIX}save file...
+	if [ $((NSIZE+204800)) -gt $FREEBASE ]; then	# 204800 = 200K slack space
+		FREEBASE=`df -B 1 | grep -m1 "^$BASEDEV" | tr -s ' ' | cut -f 4 -d ' '` #110212 Jemimah: this is very slow; try not to check every iteration #110222 shinobar: fix for pup_ro10 and more
+		if [ $((NSIZE+204800)) -gt $FREEBASE ]; then	#110212 Jemimah.
+			touch /tmp/snapmergepuppy-nospace  #110222 shinobar
+			break
+		fi
+	else
+		FREEBASE=$((FREEBASE-NSIZE)) #110212 Jemimah: keep track of the worst case
+	fi
+ 
+	if [ -L "$N" ];then
+		[ "`readlink "$BASE/$N" 2>/dev/null`" = "`readlink "$N"`" ] && continue
+		rm -rf "$BASE/$N"	# SFR: in case if folder has been replaced with a symlink (cp won't overwrite a dir with a symlink)
+		cp -af "$N" "$BASE/$N" 2>>/tmp/snapmergepuppy-error
+	else
+		if [ ! -e "$BASE/$N" ] ; then
+			cp -af "$N" "$BASE/$N" 2>>/tmp/snapmergepuppy-error
+		elif [ ${NCTIME%%.*} -gt `stat -c %Z "$BASE/$N"` ] ; then
+			cp -af "$N" "$BASE/$N" 2>>/tmp/snapmergepuppy-error
+		fi
+	fi
+done
+
+# =============================================================================
+
+sync
+cd "$WD"
+
+# =============================================================================
+
+error_msg () {
+	if [ "$SHUTDOWN" = "no" -a "$XRUNNING" = "yes" ];then
+		export DISPLAY=':0'
+		/usr/lib/gtkdialog/box_splash -timeout 30 -close box -icon gtk-dialog-warning -bg red -text "$1"
+	else
+		echo "$1"
+	fi
+}
+
+export LANG="$OLDLANG"
+ERRSTATUS=0
+
+if [ -f /tmp/snapmergepuppy-nospace ]; then #110222 shinobar
+	ERRMSG="$(gettext 'WARNING!
+Unable to save all files. You need to delete some.')"
+	error_msg "$ERRMSG"
+	ERRSTATUS=1
+fi
+
+sed -i '/No such file or directory/d' /tmp/snapmergepuppy-error	# discard errors caused by bad timing
+
+if [ -s /tmp/snapmergepuppy-error ]; then	#140102 SFR
+	ERRMSG="$(gettext "WARNING!
+There were some errors detected.
+(see '/tmp/snapmergepuppy-error' for details)
+Filesystem check of the savefile (pfix=fsck) is highly recommended.")"
+	error_msg "$ERRMSG"
+	ERRSTATUS=1
+fi
+
+exit $ERRSTATUS
+
+# =============================================================================
diff --git a/woof-code/support/mk_iso.sh b/woof-code/support/mk_iso.sh
index 2c73e0e2278..0b6e46159c7 100755
--- a/woof-code/support/mk_iso.sh
+++ b/woof-code/support/mk_iso.sh
@@ -255,6 +255,9 @@ title pdev1=sdc1      The boot partition.\nPress Enter to go back to main menu
 title psubdir=/pathto/slacko64 Path in which the OS is installed.\nPress Enter to go back to main menu
   configfile /boot/grub/menu.lst
 
+title punionfs=aufs Union file system to use.\n aufs overlay
+  configfile /boot/grub/menu.lst
+
 title psavemark=2     Partition no. (in boot drive) to save session to.\nPress Enter to go back to main menu
   configfile /boot/grub/menu.lst