Thanks to all for the great help. I thought I'd give a recap of my issue/solution in case it helps anyone else. I used the command line version of the tool as I thought it would be easier to just run a batch file in the future.
I have been running Logitech Media Server for many years from Windows. Recently I moved all my music to a Synology NAS and was having trouble getting the Media Server to "see" my content on the box. So I installed Logitech Media Server on the Synology NAS itself (supported right out of the box with just a few clicks!). Everything was working great except for the fact that all my playlists were being held captive by iTunes in Windows.
My solution was to download iTunes Export from here:http://www.ericdaugherty.com/dev/itunesexport/
I grabbed the command line version so I could write a batch file to invoke it easily. Here's the contents of my command file:
"C:\Program Files (x86)\Java\jre6\bin\java" -jar itunesexport.jar -outputDir=\\diskstation\Media\Music\iTunes\Playlis ts -musicPath=/volume1/Media/Music/iTunes/Music -musicPathOld=C:\Media\Music\iTunes\Music -fileTypes=ALL -separator=MAC -includePlaylist="Brad 4 Star Sorted,Brad 5 Star Sorted,Kids 4 Star"
In the above command line the musicPathOld is where iTunes "sees" all my files from Windows, i.e. I created a softlink at C:\Media that points to \\diskstation\Media. The musicPath is the path that gets inserted into the m3u files, which is where Logitech Media Server "sees" the music locally on the NAS. I only wanted to create a few playlists as indicated by the includePlaylist. If you get rid of that part it generates all the playlists. I also have my iTunes library xml in the default location so didn't need to specify anything there.
Anyway, I hope this helps someone else having a similar issue. Now if I want to re-create the m3u files I simply run the batch file and then rescan playlists.