just read your post again. I think i understand what your saying better now.
The list on the main xm screen is not updateing with the favorite list?
Im not really sure how the favorite thing works, i think it opens a favorite list popup (which i just noticed is not skinned). From there i dont know what happends.
In SkinCommands.txt the fav button is defined as
"XMFAV" - Cycles through Favorites XM Lists
Thats all i know about it.
Can someone with working XM give me the run down, step by step on what happens when you click the "FAV" button in the XM screen or Sirius screen?.