Oh boy, I really am looking forward to my stay here now
Anyway, I have noticed the same key card problem at several Marriott hotels in Germany, ie. they give you a late check-out but key card still stops working before your extended check-out time. Likewise, only in Germany have they missed my Platinum status and only given the benefits after I point it out. And only in Germany have they missed I'm using my corporate rate and tried to bill the rack rate at check-out.
I'm starting to lose my faith in German efficiency.