Hi Ernst,

>i'm using black on grey rgb(0,0,0) on rgb(192,192,192)(selected with the color picker)for testing but have the same problem with other (standard-)colors and on different graphic adaptors.

It definitly sounds like a video driver problem. Are those video adapters maybe all from the same manufacturer or do they use the same driver? Does the problem persist if you use the generic VGA 640x480 video driver that ships with Windows?

Christof