Ubuntu Customization Kit fails with error messages

Ubuntu Customization Kit has not been developed for years, and has the note
"!!!PROJECT DISCONTINUED!!!"
on its Launchpad homepage https://launchpad.net/uck

Recent Ubuntu releases differ from previous ones in a manner, that certain steps of UCK now fail.

I can give some advice:
     1. deselect all language packages that contain the string -touch- in their name
     2. modify /usr/lib/uck/customization-profiles/localized_cd/customize_iso and change in line ~84 (the longest line in the whole file) the part

... $(zgrep gz ...
      into
... $(zgrep xz ...

and three lines later
      change

tar xfz *.tar.gz ||
       into
tar xfJ *.tar.xz ||

You might read recent questions and bugs related to UCK on Launchpad. These recommendations (and some more) have already been given to other persons with similar problems.