Rating changes on an iPod aren't reflected in MC like they used to. I don't know if I can reproduce this, but first, I upload songs to the iPod, then I import to the library using the iPod as the source with subfolders. Then I synchronize to put my smartlists on. I have the smartlist for unrated songs; I go through the list and listen to each one and rate it accordingly. After that, when I try to synchronize, MC deletes all the songs with the changed ratings and then it gives an error about not being able to find the files it just deleted. Going further, I reupload the songs that were deleted (I started testing using only one song with a rating change so there's less to re-upload). I restore a backup library that just has the smartlists already made but nothing imported yet. Then I import again. And no matter how many times I sync, rate, sync, rerate, every time I rate a song then try to sync that change within MC (sync data to MC is always checked) the rating is reset to have no rating.
Everything was working fine for me at least a month ago, before problems erupted about the database being corrupted or having all songs and smartlists visible in MC10 but not in the iPod. I'm really unsure of the build because there were so many, but I'm pretty sure it was just before tag altering through the iPod database screen was disabled. If MC10 doesn't seem to be going where someone like me would want it to go, can you let me know that version of MC10 and let me download it somewhere? Everything worked brilliantly before, mostly. Cleared the library every time I uploaded new files, reimported, synced, synced again whenever I changed ratings. I only occasionally had a problem with file duplicates showing up and I'd happily trade that problem with this.