tuffest part, is getting the right "purple" in the background that HTC uses for the transparancy. If you change the color count up to play with it, almost alway when you change it back to 256 it uses the wrong shade. You can get around that by editting sites that have the right colors from the start, or you can learn how to use the alpha channels thata give you that illuminated look you can use now.
Good Luck!