haha bad timing.
I had just deleted the tables and reinstalled the program out of sheer desperation. Figures that when you guys checked it out lol.
OK, so it just won't make thumbnails, despite GD2 being selected. Its super weird, because it did it once, then never again.
Could this also be a file that wasn't uploaded properly? I redownloaded the package and uploaded that, just to make sure. Didn't help.