ok, is really simple.
1) backup first your current folder, before you make some mistake.
2) the all object pictures are located to: usr/mediastation/current/usr/media
Inside the media folder, you can find the all images object used on the OS.
3) if you like to edit some object, first recall from the OS the desidered GUI, then browser to the "media" folder untill you find the same object used.
4) After found the object picture interested, open it with photoshop:

5) edit what you like and then Save as always under .PNG format and interlaced mode.
6) NEVER change the name of the file or then the OS can not loading
7) NEVER change the size pixel or the global GUI page will brocken.

When you redraw some nice GUI, then just send me the edited pictures object that I load on my SVN server and then will be compiled for the new OS update.

I never tested, BUT I think the QT interface is also able to use the .gif animated object.
Just make me one .gif for testing, I can edit the code to change the same .png object to .gif, recompile and we can see if is working.