blinking graphical frame

Hello

I have a Sony VPCYB1 (AMD + graphic card=HD6310) with ubuntu 64 bits installed. I installed DraftSight successfully (manually, copying dirs to right places and using preinst and postinst scripts)

When I launch it, the graphical frame blinks between black (graphical background color) and gray (menu background color) when I move the mouse.

With the gray color I cannot see drawings : its only gray. It oftens staysgray so I can't really use it.

How to stop this blinking gray ?

Regards

Emmanuel