For me there was no migration at all, because before Connecter i didn't have any library. All my assets where lying in few folders, losely separated by categories. To find something, was nearly impossible, so i was always using the same few assets in all my works. With the help of Connecter, i discovered so many models or textures, i wasn't even aware that i have them. Most of them were deleted immediately, because they were horribly outdated :]
Lack of proper documentation is a bit of issue, but basics are pretty easy to grasp and with time you will discover more advanced features. Also Connecter team is very friendly and open to discussion, you can find them on trello or on facebook.