Ok I managed to flash to 1.1 and then got HighGFX running v40.6. Performance in 1024x768 is good when you drop the colors right down.
I have a few problems with V0.9 of the config tool. The Screen position arrows don't seem to do anything and I can't seem to work out how to configure it to run at a higher refresh in WB (eg 60hz+) and a lower one for games (50hz to get rid of the judder)....anyone manage this?
I've also got a weird bit of corruption on the very last line of the display (flickers on and off?).