If you say intel, then it is a driver issue.
Argh! ITS NOT A DRIVER ISSUE! Stop telling me its a driver problem when I know 100% it isn't! Everything else for GL works perfectly. Blitzmax GL stuff does not work. It is not the drivers! OK?! :/If you bothered to actually read threads instead of just bombarding the forums with a hundred replies a day and an opinion on everything, you'd already know its Intel GMA hardware (actually you would have known that when you pointlessly 'tested' an Intel GMA problem on Nvidia hardware last week in this very thread).
This would clarify if it's a drivers problem or an incompatibility with the way BlitzMax handles OGL stuff.
This is what Mark said it is, above (shared GL contexts). Can it be fixed? Mark says "maybe".