That happend to be a while ago too. Maybe forumotion is having problems again? A while ago, i couldn't upload avatars and i other people did too at forumotion, so i had to wait it for them to fix it, and was wierd my avatar just shows blank but i see other's people avatars
Later, it got fixed. Unsure if thye fixed it now Does it work now? Beacause i see the upload button, if not i'm not sure