Use your own Apps Icons (untested):
From:
https://4pda.to/forum/index.php?show...ost&p=76488379
Draw 2 icons, in bmp format, 256 gradations of gray, uncompressed.
desktop_app_applicationname.bmp is unpressed
desktop_app_applicationname_f.bmp - pressed
Put in the "system/resources/Line" folder.