I've never really been able to manage user-libraries particularly well in Eagle. The problem becomes exacerbated when moving projects from computer to computer, and even worse when trying to maintain some sort of version control. This came to a head yesterday when I did an Eagle version update, and simply rolled it back rather than dealing with issues the right way (complicated by trying to do some pro-bono consulting on a feel-good project that I need to keep entirely separated from the resources of my employer).
The closest I've come to being anywhere near happy is to maintain a user library for each and every project, and include it as part of the subversion set. This, however, has some real limitations, but boy, it certainly makes things unambiguous.
Is there a good way to maintain a user library tree that's friendly for portability and version control?