Just a few basic codes to help customize your profile.These are the ones I used so thats how I know they work.

Message box= [style ].form_textarea{background:url(inserturlhere)}[ / style]

Background(via Biography and stuff) =[style ]TD{background:url(inserturlhere);}[ / style]

Body(via Page background.) = [style ]body{background-image:url(inserturlhere)!important;}[ / style]

Colors= [style ]TD{background-color:#1;color:#2;}[ / style]

Image= [image]urlhere[ / image]

Tips
Remove all spaces.Remove #1 and #2 and replace with actual colors.