In the just released 9.0.2 update for iTunes some changes have been made to how iTunes LPs are handled. This causes iTunes to refuse to add some community created iTunes LPs. If you are having trouble adding an iTunes LP to your iTunes music library please re-download the LP from our download page, or if you got the iTunes LP elsewhere see our Getting Started tutorial to see how you can create a manifest.xml. This file is probably missing and is now a required part of the iTunes LP format. To fix any problematic file it should probably be enough to add this file.