>I can now queue an album, or at least a playlist
>within which there are actual tracks.
>Still can't queue a playlist if there are no tracks at the
>next level down, that is, there are only further playlists.

Yes, that behaviour is intentional.. I added code to do exactly that, to avoid having recursion inside the kernel.. (generally a Bad Thing(tm), especially in kernels). So for now, I think it will stay that way.

Cheers