Very interesting. I will forward your writings to Betty Krull. She is the wife of my cousin Martin Krull. He together with my other cousin Andre Krull have researched our familie branch from Amsterdam to Loningen, Germany (a little town near the Dutch border). From what I understand is the farthest they can trace (up to now) is to the 1620's
There appears to be a Familie Crest (Krull - Mecklenburg, Schwerin): A golden shield with a blue banner across having three golden stars. Dated about late 1400's. Mind you, there are sceptics.