It's for 2k4 utcomp. ut3 utcomp has been mostly managed and worked on to be improved by Faust. Last version is utcomp3v4 (no more beta) or a last iteration of the beta like utcomp3v4b3. He never released it because "they weren't enough beta tester" and "didn't want to pay much attention to it anymore as game was dieing", also iirc there was some bugs too he cnba to fix for previous reasons.
and when i was looking for utcomp, i was looking for the installation directories.. couldn't find them until Taffy made me aware of the old README file in the file.. and let me put a little defense on this for the dense, i was looking how to install it because of the "cache" problem with utcomp, where the skins go grey and your xhairs disappear..