Anyway it appears the whole episode was a hoax, the seller's cancelled all the bids and returned to price to €1. Maybe it wasn't as NOS as we were led to believe.
there is discussion about this on the Messerschmitt Owner's Club forum and it appears that at least two posters know the seller.
I also postulated why the auction was stopped and the bids cancelled, I could reprint my postulations, pontifications and prognostications here if anyone cares.
also- it was pointed out that while the motor is a NOS SACHS motor, it is from a FULDAMOBIL and if you look at the listing it says that a used cooling shroud for a KR200 would be included if the buyer wanted it. The other problem is that apparently the gearing in the Fulda motor is different from the Messerschmitt Sachs motor.
so...could be that is why the listing was cancelled by the seller.
note: the listing was "ended" by the seller, it has not been "returned" to 1 Euro for bidding.