You also have to "corrupt" the iTunes Library.itl file (i.e. create a 0 byte file) so that it rebuilds from the XML file, otherwise it resets all of your editing. It's a pain, and slow. If you're on a ...
I'm running into this weird issue with iTunes where some songs that are listed in my library will not play and iTunes indicaes that it cannot find the song - sort of like a broken link or bad path or ...