Ok. Here's how I interpret the recall description:

A sensor on the Actuator board sends the FDC the position of the transmission on vehicle start. Cracks on the Actuator board cause a voltage drop on the position sensor so that the position determined by the FDC is incorrect. The FDC then attempts to position the transmission actuator properly and it sounds like, depending on the voltage drop produced by the cracks, the transmission could be put into *any* gear! The new firmware will probably try to shift into Park first to see what voltage is returned, before determining that it is in the wrong position. Why it is not easier to replace the Actuator board is puzzling but I have done my fair share of fixing hardware problems in software.