hi, thanx for replying so it has something to do with vista64 and (maybe vista in general?) in combination with chrome, will check this out further..
as for low framerate in chrome, last week chrome decided to disable the GPU Accelerated Canvas 2D at default, no idea why but they did, you have to manually enable it, put this in url chrome://flags/
not sure why you getting good framerate in firefox tho, for me its really bad, especially physics, but i havent installed the construct webgl version, i rather wait a little