Update – certainly got it working – but not as quite straightforward as I had thought! There seems to be some problem with large m3u files. Small files with only one or two entries in appear with no problem, but I have been playing with files with around 100 entries!
If there are no valid entries at all, either because they are commented out or not unixly correct, then itunes will not display the file, although other playlists are displayed. If there are some valid entries, itunes diplays the playlist and the valid entries. No problem there – however the Roku is a different matter!
It seems very sensitive to the correctness of paths – an incorrect path in an m3u file stops it loading any playlists at all, although it will connect to the server OK. However there are occasions when it will connect to the server but not load playlists even though the file is correct – the only solution then is to restart mt-daapd. More strangely, sometimes after re-writing the playlist to the slug, the Roku won’t connect to the server at all, unless the server is re-started! (Sometimes 2 or three times)
I won’t even hazard a guess as to why this is – or if the situation will change with the next release of Roku softwatre (currently in beta testing)
For the record I am using 0.2.4-1 on unslung 5.5 The m3u files were edited either natively using vi, or remotely using gedit. I have also created them using xmms on a remote machine, but then all the paths need to be corrected (as XMMS creates absolute paths) using the global find and replace in gedit.
Hope that helps prevent anyone else tearing their hair out over this… meanwhile I shall continue preparation for the party for which this is being done!