do you need to make some layers, and "dinamic" objects (animated are more grateful to view). If you wish to make animated objects, you can apply any technic! Ultimatelly i use 3d programs (also other people), with any 3d program you can do this. The most used technic are using a 2d program, to make the composition of any frame of the animation.
In any way, you need to apply your imaginery!
Look Baxxi and Frogboy skins to see how they make good themes!
If you wish to see good animated objects/zoomers, look the mormegil's skins he's the master!), also my skins if you wish.
DesktopX objects are zipped objects, so if you change the extension as .zip, and uncompress the file, you can open the graphics contained in the objects. See the objects how are released. NOTE: BMPs & PNGs uses different systems to apply alpha channels