Sorry, didn't see your answer...
Unigine Heaven has a problem natively on radeon for me too. Maybe it's a mesa problem? I will soon test with optimizations on -O1 because I had a problem with lib32 mesa that wine only works with -O1 and not with -O2 since llvm 3.0.
I will also try the mouse settings, but probably I'll wait for the weekend because I only boot windows on weekends for playing and prefer working with my full RAM during the week.
~ % unigine-heaven
Fullscreen? Please enter 1 or 0. (1 = yes, 0 = no)
Video width? e.g. 1024
Video height? e.g. 768
Engine::init(): can't create log file
Engine::init(): clear video settings for "Gallium 0.4 on AMD REDWOOD 2.1 Mesa 8.0-devel (git-9783bba)"
Set 640x480 windowed video mode
X Error of failed request: BadRequest (invalid request code or no such operation)
Major opcode of failed request: 154 (GLX)
Minor opcode of failed request: 34 ()
Serial number of failed request: 46
Current serial number in output stream: 4
I may mention again that I "only" use the VMWare player, so not even the commercial product.