Moving to a new computer
Moving data to a new computer can be a challenge.
When it comes to moving beaTunes to a new computer this is what you should do:
In beaTunes select your library and choose Export from the File menu. It will create a (probably fairly big) XML file that should allow you to import (also in the File menu) the beaTunes data on your new machine. When doing this, please make sure to use the same beaTunes version!
As an alternative, if you have always embedded data into the files with beaTunes (using the option in the general prefs), you can run the corresponding analysis task for importing that kind of stuff in beaTunes.
Please understand that when moving to a new computer, all songs lose their unique ids. It is through these ids that beaTunes associates data with iTunes songs. The import function tries to re-establish that link. It's the nature of the beast that it does not always work 100%. It should work reasonably well, though. If you want to support the matching process, make sure that most if not all songs have PUIDs or other online resource IDs.
(this article was written for beaTunes 2.0)