UCK Error: Unable to extract gfxboot-theme-ubuntu source package

[Pierre]

UCK in Ubuntu 16.04:

I am unable to build the ISO because of a gfxboot error. Please help. Here is the build.log:

Mounting ISO image...
mount: /dev/loop0 is write-protected, mounting read-only
Unpacking ISO image...
Unmounting ISO image...
Mounting SquashFS image...
Unpacking SquashFS image...
Unmounting SquashFS image...
Removing win32 files...
Creating apt cache...
Creating root home...
Mounting /proc
Mounting /sys
Mounting /dev/pts
Mounting /tmp
Mounting /home/.../tmp/remaster-root-home
Mounting /home/.../tmp/remaster-apt-cache
Mounting /run
Mounting /home/.../tmp/customization-scripts
Copying fstab/mtab...
Creating DBUS uuid...
Creating user directory...
Copying X authorization file to chroot filesystem...
xauth: file /root/.Xauthority does not exist
xauth: file /home/.../.Xauthority does not exist
Deactivating initctl...
mv: cannot stat '/sbin/initctl': No such file or directory
Deactivating update-grub...
Deactivating grub-probe...
Hacking grub-probe postinst/postrm...
Remembering kernel update state...
>> Customizing: Ubuntu 16.04, 4.4.0-31-generic x86_64
Get:1 http://security.ubuntu.com/ubuntu xenial-security InRelease [94.5 kB]
Hit:2 http://archive.ubuntu.com/ubuntu xenial InRelease
Get:3 http://archive.ubuntu.com/ubuntu xenial-updates InRelease [95.7 kB]
Get:4 http://security.ubuntu.com/ubuntu xenial-security/main amd64 Packages [138 kB]
Get:5 http://archive.ubuntu.com/ubuntu xenial-updates/main amd64 Packages [383 kB]
Get:6 http://security.ubuntu.com/ubuntu xenial-security/main Translation-en [57.0 kB]
Get:7 http://security.ubuntu.com/ubuntu xenial-security/universe amd64 Packages [41.5 kB]
Get:8 http://security.ubuntu.com/ubuntu xenial-security/universe Translation-en [25.1 kB]
Get:9 http://archive.ubuntu.com/ubuntu xenial-updates/main Translation-en [145 kB]
Get:10 http://archive.ubuntu.com/ubuntu xenial-updates/universe amd64 Packages [324 kB]
Get:11 http://archive.ubuntu.com/ubuntu xenial-updates/universe Translation-en [111 kB]
Get:12 http://archive.ubuntu.com/ubuntu xenial-updates/multiverse amd64 Packages [5488 B]
Fetched 1421 kB in 5s (268 kB/s)
Reading package lists...
Installing language packs ()...

Please choose customization action
1) Run console application
2) Continue building
Your choice (1..2)> /tmp/customization-scripts/customize: line 144: [: too many arguments
CHOICE='Run console application'
Starting console application...

Please choose customization action
1) Run console application
2) Continue building
Your choice (1..2)> /tmp/customization-scripts/customize: line 144: [: Continue: binary operator expected
CHOICE='Continue building'
Done
Restoring kernel update state...
Reactivating initctl...
mv: cannot stat '/sbin/initctl.uck_blocked': No such file or directory
Reactivating update-grub...
Reactivating grub-probe...
Reactivating grub-probe postinst/postrm...
Removing /home/username directory...
Removing generated machine uuid...
Removing generated fstab/mtab...
Removing crash reports...
Unmounting /home/.../tmp/remaster-root/var/cache/apt...
Unmounting /home/.../tmp/remaster-root/tmp/customization-scripts...
Unmounting /home/.../tmp/remaster-root/tmp...
Unmounting /home/.../tmp/remaster-root/sys...
Unmounting /home/.../tmp/remaster-root/run...
Unmounting /home/.../tmp/remaster-root/root...
Unmounting /home/.../tmp/remaster-root/proc...
Unmounting /home/.../tmp/remaster-root/dev/pts...
Cleaning up temporary directories...
Running ISO customization script /home/.../tmp/customization-scripts/customize_iso...
--2016-09-09 14:33:52-- http://archive.ubuntu.com/ubuntu/ubuntu/ubuntu/dists/xenial/main/source/Sources.gz
Resolving archive.ubuntu.com (archive.ubuntu.com)... 91.189.88.149, 91.189.88.161, 91.189.88.162, ...
Connecting to archive.ubuntu.com (archive.ubuntu.com)|91.189.88.149|:80... connected.
HTTP request sent, awaiting response... 200 OK
Length: 1102678 (1.1M) [application/x-gzip]
Saving to: ‘/tmp/tmp.HkAAkpbu1r/Sources.gz’

     0K .......... .......... .......... .......... .......... 4% 209K 5s
    50K .......... .......... .......... .......... .......... 9% 198K 5s
   100K .......... .......... .......... .......... .......... 13% 237K 4s
   150K .......... .......... .......... .......... .......... 18% 247K 4s
   200K .......... .......... .......... .......... .......... 23% 310K 4s
   250K .......... .......... .......... .......... .......... 27% 280K 3s
   300K .......... .......... .......... .......... .......... 32% 306K 3s
   350K .......... .......... .......... .......... .......... 37% 353K 3s
   400K .......... .......... .......... .......... .......... 41% 374K 2s
   450K .......... .......... .......... .......... .......... 46% 395K 2s
   500K .......... .......... .......... .......... .......... 51% 389K 2s
   550K .......... .......... .......... .......... .......... 55% 402K 2s
   600K .......... .......... .......... .......... .......... 60% 402K 1s
   650K .......... .......... .......... .......... .......... 65% 390K 1s
   700K .......... .......... .......... .......... .......... 69% 401K 1s
   750K .......... .......... .......... .......... .......... 74% 389K 1s
   800K .......... .......... .......... .......... .......... 78% 402K 1s
   850K .......... .......... .......... .......... .......... 83% 399K 1s
   900K .......... .......... .......... .......... .......... 88% 391K 0s
   950K .......... .......... .......... .......... .......... 92% 402K 0s
  1000K .......... .......... .......... .......... .......... 97% 243K 0s
  1050K .......... .......... ...... 100% 928K=3.3s

2016-09-09 14:33:56 (326 KB/s) - ‘/tmp/tmp.HkAAkpbu1r/Sources.gz’ saved [1102678/1102678]

--2016-09-09 14:33:56-- http://archive.ubuntu.com/ubuntu/ubuntu/ubuntu/pool/main/g/gfxboot-theme-ubuntu/
Resolving archive.ubuntu.com (archive.ubuntu.com)... 91.189.88.161, 91.189.88.149, 91.189.88.162, ...
Connecting to archive.ubuntu.com (archive.ubuntu.com)|91.189.88.161|:80... connected.
HTTP request sent, awaiting response... 200 OK
Length: 5525 (5.4K) [text/html]
Saving to: ‘index.html’

     0K ..... 100% 532K=0.01s

2016-09-09 14:33:56 (532 KB/s) - ‘index.html’ saved [5525/5525]

tar (child): *.tar.gz: Cannot open: No such file or directory
tar (child): Error is not recoverable: exiting now
tar: Child returned status 2
tar: Error is not recoverable: exiting now
Unable to extract gfxboot-theme-ubuntu source package

ProblemType: Bug
DistroRelease: Ubuntu 16.04
Package: uck 2.4.7-0ubuntu2 [modified: usr/lib/uck/customization-profiles/localized_cd/customize]
ProcVersionSignature: Ubuntu 4.4.0-34.53-generic 4.4.15
Uname: Linux 4.4.0-34-generic x86_64
ApportVersion: 2.20.1-0ubuntu2.1
Architecture: amd64
CurrentDesktop: LXDE
Date: Fri Sep 9 14:42:05 2016
InstallationDate: Installed on 2016-06-01 (99 days ago)
InstallationMedia: Lubuntu 16.04 LTS "Xenial Xerus" - Release amd64 (20160420.1)
PackageArchitecture: all
SourcePackage: uck
UpgradeStatus: No upgrade log present (probably fresh install)