Sansa Clip+ - Playlists won't play!

[Madcobra]

I've just installed Rockbox, but despite the Manual claiming "3.1.7. Basic concept - Rockbox is playlist oriented." nowhere does it explain HOW to play a playlist, nor does it provide any example of the required playlist entries (the OEM Clip firmware, playlist entries must NOT have a path and the playlist file itself must be in the same directory as the music files it calls - again not documented).

I can find and select my existing playlists and the corresponding mp3 files are still in subfolders of /MUSIC but my playlists  (I moved them to /Playlists) no longer work! Choosing a playlist from Playlist Catalogue and pressing either Select or Right shows the playlist's contents. Any further combination of Select or Right goes back to Main Menu.
Individual mp3 files play OK when selected from Files in the main Menu.
 
The installation has added the directory /##MUSIC# with a set of sub-folders containing some unwanted 'music', albums and other files on my Clip. I can easily delete the unwanted content, but where must my music and playlists sub-folders be in order to work, in /##MUSIC# or in the original /MUSIC?

[saratoga]

I've just installed Rockbox, but despite the Manual claiming "3.1.7. Basic concept - Rockbox is playlist oriented." nowhere does it explain HOW to play a playlist,

The next sentence explains that playlists are generated automatically as you select files. Basically, as you're selecting songs or queuing up albums you are creating and listening to a playlist.

I can find and select my existing playlists and the corresponding mp3 files are still in subfolders of /MUSIC but my playlists  (I moved them to /Playlists) no longer work!

An m3u file is a text file listing files to be played. If the file paths are relative to the m3u file location, you'll need to move the playlist and the music files together, or the paths will break. If they're absolute paths that won't matter.

The installation has added the directory /##MUSIC# with a set of sub-folders containing some unwanted 'music', albums and other files on my Clip. I can easily delete the unwanted content, but where must my music and playlists sub-folders be in order to work, in /##MUSIC# or in the original /MUSIC?

##MUSIC# is the Sandisk firmware's files in MTP mode IIRC. If you're not using the Sandisk firmware you can delete it. Music is where it puts them in MSC mode. You can delete that or keep using it. In rockbox the choice of directory doesn't matter.