I have Matrox g550 graphic card and until i shut down HW acceleration (one level above off), picture is totally messed up (the map, tiles in the left column are ok). Nothing serious, but i think it is good to inform you.
As Matrox cards are usually more reliable than NVidia or ATI, I guess there is something strange in the way I handle the drawing ... but since I can't reproduce that error, it will be somewhat problematic to trace it down :-/
When I have some time I will take a look if I find some less logical parts in the source ... maybe a shader or something.
Well, as i said, dont waste time on that, i can always turn that thing off. Anyway if you want some testing and reports, just ICQ me and we can test for you anything you need.