Here is a guide which seems promising. Unfortunately, to begin with, there does not seem to be a master of classical Latin here. And then very rare books and dictionaries are necessary and “but anyone wishing to engage seriously with the study of Medieval Latin will find that a knowledge of French and German is absolutely necessary.”
Anybody up for it ?
I found a few descriptions of images and images from it and I am very curious.
I for one would be surprised if there were not even one hidden gem to be found.