I don't know if this is related or not, but I know that when I post (I just paste text in, no tinyMCE or uploaded file), a box always pops up when I click post... I can't even remember what it's asking for now, but I've learned to just ignore it because the chapter will post anyway. If I click on the box, it doesn't upload right. I'll let you know what the box says next time I have something to update LOL.
Sorry, I know that was incredibly vague LOL.