OK, so I decided to give up a few more minutes testing this playlist thing...
After over an hour I've decided I still don't know exactly what's going on, but here's what I've seen.
The files I have problems with have a filename that starts with a number. I don't think it's important, but all of my files currently have the "Title" field exactly the same as the filename. (Simply because I am still uploading using PlayCenter due to the 60 char. bug - still waiting for that 9.0.32
)
I've notice that if I actually TRANSFER the files to the Nomad through MC, then the file will later be immune to further problems. Hence, if the file doesn't already exist on the nomad, I can transfer via drag and drop or the synchronize without incident. The files are transferred and also added to playlists. Everything still works even if I change the name field or chose either Name or Filename as the title field.
However, it seems like when the file exists already (having been uploaded through PlayCenter), if I try to transfer the file, either through a drag and drop, or through sync, these files that start with a number do not get added to the playlist.
However, like I said above, If I delete the problem files, then transfer them again through MC, everything will work as expected. I will be able to create playlists with these files by using the sync even if they exist already on the Nomad.
So... maybe there is some wierd incompatibility with files uploaded through PlayCenter, and/or other software, though it is beyond my ressources to know how this would manifest...
Anyways, I guess dedicated MC users will not run into this, but until other parts of MC are fixed (and there's lots of fixing to be done!
) I will still need to work with other software. All in all, there's a bug somewhere and it should be squashed...