He refused to help you because you bought them used? That's kind of stupid since he is technically selling used cams to begin with. I think somebody posted a copy of the instructions that come with the cams. I'll see if I can find it.
It has nothing to do with high lift or geometry. The cam is a regrind, which means they remove material from the base circle of the cam. The lifter might then be too short because of the material that was removed, a shim can solve this. The...