The mechanic that we used to install the ECM has That Machine, the giant coding-machine-thing that BMW and Mercedes uses, so it was done. And we have a tool that can read and reset BMW stuff (sorry for the non-technical jargon, guys). But we still couldn't figure out why the dash lights stayed on (brakes, abs...), and he suggested a shorted or loose wire. The car was driven home from the shop. When hubs started checkign wires, then the fan went on, lights started to flicker...and nothing. He's been scouring this website, and is in the process of heading to O'Reilleys for a Crankshaft sensor, which, he hopes, doesn't have to be coded (since it's not a special-order piece, it probably doesn't).