I've followed the instructions for the top-down shooter to add the background but used my own image instead, and I got this:
<img src="http://www3.picturepush.com/photo/a/8400686/640/8400686.png" border="0" />
I checked the picture in Paint, and it had no white boarders. It is a PNG. Any help is very welcome, and I'm sorry if this is the wrong forum.