I read about it online and think it was because I ran Tool32 in Windows 7, but not as administrator. I suspect that was the problem. Make sure you run Tool32.exe as administrator (not just by double clicking file).
Still reading about coding and playing with software. I actually don't have the cable yet (on order). I don't want to screw anything up. Sincere thanks to Shawn Sheridan for all of the support on the forums. He seems to always be helping others and a great asset to the BMW community.
Coding still seems pretty daunting to me - perhaps it's my lack of German