Hmmm… I had the same problem, but managed to solve it. I should be able to help you.
Do you have both the sauerbraten and sauerbraten-data packages installed (Packman repo).
Do you have the ~/.sauerbraten directory present?
In my case, I didn’t originally have the data package installed. Even after I did, it still wouldn’t start from K Menu. After looking at the sauerbraten.sh script in /usr/bin, I realised that I needed to delete the .sauerbraten directory. The script then recreates it with links to the /usr/games/sauerbraten and usr/share/games/sauerbraten directories, as required. However if .sauerbraten exists already, it will not add links, so in my case the data packages were not being included. See script below:
linux:/usr/bin # cat sauerbraten.sh
if ! -d $CUBE_DIR ]; then
mkdir -p $CUBE_DIR
ln -s /usr/games/sauerbraten/* .
ln -s /usr/share/games/sauerbraten/* .
rm servers.cfg 2> /dev/null
exec ./sauer_client $*
I could have done this housekeeping manually. I stumbled on the problem after executing ./sauer_client from a console with success.