Good writeup.
As for the charts you mentioned, some actually exist on this page but I don't think many people have noticed:
http://www.vishnutuning.com/BMW_support.htm
Specifically...
Flowchart:
http://www.vishnutuning.com/images/BMW/335flowchart.jpg
Engine codes:
http://www.vishnutuning.com/images/B...oublecodes.jpg