While Mezzmo works very well to recreate my iTunes playlists, my Sony Blu-Ray player only supports a fixed sort order (seems to be album: track no; if playlist: alphabetical). That's fine if you play albums, but we like mix playlists. I found that if you export the playlist from iTunes into a m3u playlist, then create in Mezzmo as a linked playlist, the sort order is retained. There is a downside with the linked playlist as there is a distinct pause between songs. That pause was quite long (approx 10 seconds) when the songs were different types (e.g., mp3 followed by an m4a that requires transcoding to lpcm). That seems logical as more info has to be processed. Note that all the songs were already in my Mezzmo library from the original iTunes library load.

At first, I could not get an exported iTunes m3u playlist to link into Mezzmo. The playlist would link without a problem, but no songs would be listed. I noticed that a playlist generated by WinMediaPlayer did link and list the songs. The exported iTunes playlist had the normal m3u header followed by the songs listed with their specific path:
"C:\Documents and Settings\All Users\Documents\My Music\iTunes\iTunes Music\The Doors\The Doors\02 Riders On The Storm.mp3"
However, the successful playlist had a relative path:
"..\iTunes\iTunes Music\The Doors\The Doors\02 Riders On The Storm.mp3"
(My playlist is in a folder at the same level as the iTunes folder)

Once I revised other playlists to the relative path, they all worked. Note that I don't have my documents folder in the traditional location but in all users. Likewise, here all the songs were already in my Mezzmo library.