I have the vast majority of my iTunes library on a NAS device. When I first got my MBP I set the library's location to the folder that I had moved off one of the desktops to the NAS. Everything works fine. However, it seems that the library location will reset itself to the local location on the MBP (possibly whenever I run iTunes when I'm not on this network). So, if I add files to the iTunes when I'm not on this network, they get placed into the local library. That's all well and good, but my question is: How can I offload the files from my local library to the main library residing on the NAS? My goal is to be able to keep all the media files on my NAS and be able to delete them from the MBP.