When I try to play RTCW MP on my older Mac (with OS 9.2), it just stops loading when loading a level.
I can acces the server browser, connect to one, but it stops loading when about 1/4 is done, and I have to reboot.
Haven't got any problems playing it on my own Mac (with OS 10.1.5).
I tried deleting the "wolfconfig_mp.cfg" files, but that didn't change a thing.
RTCW requires 500 MHz, the old one has 450 MHz, so I doubt that would be the cause.