I have the mod UI Enhanced and it crashes whenever I try to add 15 bots on any map. It sometimes doesn't appear and just says "ioquake3.exe has stopped working". It crashes when I add the 11th bot sometimes, it crashes when I add the 13th bot sometimes and most of the time, it crashes when I add the 15th bot. When I searched for the file q3config.cfg in the ioquake3 folder, I couldn't find it, so I don't know if Ioquake3 comes with a q3config.cfg file. I tried removing a bunch of pk3's out of the baseq3 folder, and it still crashes. I am running UI Enhanced 2.0 and I am running Q3A Point Release 1.32.
On the 28th Nov, 2001, the source code for the UI Enhanced mod was released. Here is the link: quakewiki.net/archives/code3arena/ The link to the code however is dead.
It may be possible to find a copy of the source and fix the bug yourself.