Playlists aren't represented by directories and symlinks on the empeg-car disk. Every track is stored in a single directory along with playlist files. Playlists are stored as a list of all the contained tracks and playlists. One modification to a playlist causes the entire playlist to be downloaded (this doesn't take long - it's only four bytes for each track in the playlist).

When emplode downloads the database from the unit any tracks that aren't referenced are automatically added to the Unattached Items playlist so that they can be moved elsewhere - if you've suffered a failed download then you should check this playlist.

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Mike Crowe
I may not be speaking on behalf of empeg above :-)