Other problems that I see likely to be an issue with Quake III on a Live DVD if it works at all:

  • Everytime the group that you play with wants to add a map or even a skin, you have to remaster.

    You can't make configuration changes (or at least can't save them), including video settings, control settings, sensitivity adjustments, key definitions, music volume, and so on. This seems something that you very well might need if your intention is to have a copy of Q3 on Live DVD that you can carry from system to system. (UnionFS might help you here, but that involves more overhead.)

    Other applications that you use with Quake III like XQF, xchat, Teamspeak may have their own need to write to their setup files.