hi there, I have the same problem on my Vista laptop, the same guy answered my question but when I try to update, it says it has the latest version already, so I dont know what to do now. I find the problem is when I'm zooming in and out with a drawing tool selected
Probably this happened to me because my graphics card has poor support of opengl. Try going to tools>options and change the value for
use_software_opengl from yes to no. This worked for me.
thanks, I actually changed it from no to yes, seems better but every once in a while a very short mess up, but now its acceptable. thanks again