Hi Daniel, maybe this is somehow useful for you.
Troy Leinster, one of my classmates at Type and Media wrote an article about his experience here:
http://typographica.org/on-typography/undergrad-to-c… (View Post)
When using vfb2ufo I had problems with unnamed global guides in an ufo. That is maybe what Paul is referring to. I always make sure that those have a name otherwise the .vfb can not be reconverted pr… (View Post)