I would just like to add something....
When imageline were doing there betas for mac for 'deckadance' they had alot GUI problems when going Open GL. Don't know if this helps? but when people were posting of the problems alot of them had the same 'pop up' window problem for VST plugs on the mac with deckadance, the same that we have with plugs and reaper.
Might be worth asking the imageline team what they did to counteract this 'cutting/missing' plugin interface.
__________________
.-. . .- .--. . .-. | .. ... | --. --- .-.. -..
|