I forgot to mention I am running Windows 7 x64 with Aero turned off.
Okay, tried the first (didn't fix anything), and then tried the second which fixed things somewhat.
When I pan the canvas around it doesn't keep adding artifacts.
Now the artifacts only show up if I resize the window or switch to another application, and it seems as though sometimes the buttons and toolbars aren't being redrawn (I see a blank space where they belong, but they are redrawn if I hover my mouse cursor over them).
It's not a huge deal for me as I've gotten this far with the glitching, and otherwise the program is very stable and it's just a cosmetic issue.
btw, yEd rocks. :D