One of my favourite add-ons for quake 1 is the omicron bot, it plays great for offline multiplayer games, get it from here:-
http://www.botepidemic.com/gladiator/obots/obots.html
tiretool, that unnoficial gl quake you are using is really excellent, but i could'nt get their quake world client to work, so i went back to the regular gl version(still looks great
)Have you managed to get online with it?