Alright, when you upload be sure you don't select transparency, otherwise parts of the body will be invisible and most likely rejected.
Oh and another thing, if you want to do this without asking people you can get Paint.NET (what I used to make the background transparent). There's a magic wand looking thing that you click on, as well as a box in colors, that is next to black and white colors, that's a transparent box. I'm sure there is another way, but I prefer to do it that way.
-Because my explanation might not be as clear, here's a picture as well...