Thanks ondoho, that worked. I changed /etc/game-data-packager/alioth-mirrors to provide a URL with the required file:
Code:
# contains 1rott13.zip & 1wolf14.zip
# http://pkg-games.alioth.debian.org/game-data/
# http://localhost/
ftp://ftp.3drealms.com/share/
Then, running the command "game-data-packager wolf3d" worked, building wolf3d-demo-data_49.1_all.deb
I installed this and it works.