To use this I assume that you have already run the 'UT' or 'UT GOTY' installer as root and are now running as your usual login user. (You won't need to be root again) This is because I prefer not to make any more changes to the UT tree once the default is installed :-) which helps keep its integrity and lets you reinstall the system whilst keeping customisations safely in your home directory.
Now run 'ut' from the command prompt. The game fails to run, of course, because the maps haven't been decompressed, but, the directory structure ~/.loki/ut/ has been created in your home directory, into which the maps will be decompressed when you run my script. You will probably want to install additional .umod files now.
for N in ../Maps/*.unr.uz
../ucc decompress $N
mv ~/.loki/ut/System/*.unr ~/.loki/ut/Maps/
For this you need to install Umodpack, and this is available in Aptitude under Debian.
Rather than set Umodpack "xumod" to work as root on the /usr/local/games/ut directory, I prefer to run it on my local copy /home/michael/.loki/ut. Thereby preventing any module screwups from mandating a reinstall of ut, or a root compromise....
For this to work it is necessary to trick xumod into thinking that your local directory is the true ut root. To do this it presence checks for the file Core.u, so we simply cp /usr/local/games/ut/System/Core.u ~/.loki/ut/System/Core.u; You may run 'ut' once more to check the ini files have been copied over to user, then xumod should hopefully work as expected.