Running Mac OSX 10.6.4 + CXG 9.1 with the new wine. This on a MacPro with Nvidea GTX 285 (1024 graphic ram - set in regedit)
Still does the random black screen with a small white square in the upper left corner if you enable the Pixel Shader.
My setup runs Star Trek Online perfectly, even with Pixel Shader enabled. I guess we still don't know even what kind of problem this is.
Game runs well with pixel shader off.