So I would have to have NIN under another main playlist in order for this to work.

No, I have my "Nine Inch Nails" right off the main menu and it works.

Remember that the "Top" of the tree is the root playlist. By default, this root playlist is named "Empeg Car" or something like that, but you can rename it to whatever you want. So every single playlist you add is already a child, even if you add it at the highest possible level.

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Tony Fabris