Hi Gerben and Ron,
Actually, my family had one in the late 1960's...here in the USA...but it was called a "DKW"...ours was a convertible model...if I recall.
My brother and I took it out on the beach at Hermosa beach and we found out the door seals were not intact, got very wet, and quickly made it back to shore. It had a switch or lever to connect the drive train to a small impeller at the rear bumper...it floated real well.
Regards,
Pete... <img border="0" alt="[typing]" title="" src="graemlins/yltype.gif" />