Apparently I can't upload anything to FA with a high resolution. I've done the "change submission file" thing, but then when i do that, it breaks the thumbnail for some unexplained reason (I even made sure to uncheck the "rebuild thumbnail" checkbox). This is extremely frustrating and worrying because almost every one of the pics I've drawn is 5k x 5k or greater resolution, and I really don't want to have to go and rescale every last one of them.