Hi Toby,
the reason why some mods don't work is that with the 2.52 RS UO patch(damn when will Macsoft release it, grrrr
) has some new features or better it wipes out an victory condition bug! So you have to rewrite several files to run Covert Ops 100%. I have a fullw roking version on my HD but damn I can't distribute it! Whenever MacSoft releases it many mods will suddenly work properly! Covert Ops belong to them. May I will release a patch for all guys that have "official" the Covert Ops PC game bought. I'll check this issue with UbiSoft as soon I have done my final exams on 8.6.2001.
Bye.