So, I have OE glass (SG) not OEM - ie: no BMW logo. I suspect the previous owner had the glass replaced... but they reused the sensor.

BMW tried to reprogram it, hoping that it would fix, but no dice.

they then replaced the sensor and now it works like a charm.

because it was OE not OEM glass, it wasn't covered under warranty.

As for peoples comments about wiper behavior after ignition off, would programming that change in not fix it for you?