Importing iTunes Library into Apple Music on Monterey

Hi. You don't import the .itl file, you hold down option as you launch Music and then select the .itl file to convert it to the Music format. The common problem with Monterey is that this process just stalls indefinitely. I've successfully converted around 100 or so libraries for other people. My email address is in my user profile here. You can drop me a link to your library in iCloud Drive, OneDrive, Dropbox or similar and I will try doing the same for you. If you've been using the option-start-Music method to access the .itl file then there is a chance that it really is corrupt. If you have a recent backup of the .itl from a slightly older date it may be worth trying that one too. If your Mojave system is still running press and hold down option+cmd as you launch iTunes, which opens it in its safe mode and may do some housekeeping, then close iTunes and give it a few minutes before copying the file to your cloud location to ensure it has finished saving.

tt2

Music doesn't migrate the iTunes album artwork cache. It uses a new scheme. It may catch up, or you may want to remove the cache that it has generated which will force it to be rebuild, hopefully better on the second attempt. With Music closed delete the folder ~/Library/Containers/com.apple.AMPArtworkAgent/Data/Documents/artwork and empty the trash.

tt2