SW crashing when highlighting text

I noticed that (not all of the time) but a good majority of the time, when I select text with my mouse, at least a paragraph or more at once, either because I want to move it or delete, Sudowrite goes completely blank and all I see is the colored SudoWrite screen. I never lose anything but I have to close SW and reopen it. Not bad, but it happens enough that it disrupts the writing flow.