You can find a patched Mesa im my PPA, which updates the r300 driver to latest git before the drm2 merge.
This fixes several problems with the 200m and also improves performance.

You will now be able to start compiz, though you will get rendering glitches. But at least there are no rendering glitches in games any more...

So how do you install it then? whats the package called??
Pete

click

its the mesa packages