What is the size of the image your uploading? Height x Width

Keep in mind, this will center the image from left to right and top to bottom. If your image is small then it's hidden behind the page code () (boxes that appear on the screen with content.

To change the color from white, go to the Customize Profile screen and set a new background color to go with the image. Yes, you still have to select a color. If the color changes, then yours is working, the image is just to narrow/short see more to be seen behind the other itmes.

http://thetdz.com/TDZs will show you how it looks with a full size image uploaded.