Just tried booking a CAT 4 hotel with a megabonus cert online, but the system kept asking for a code. Wound up calling reservations and got them to book, but the reservation online shows 20,000 points?

Also mentions having to order an e-cert 7 days prior to the stay.

Is this all normal?

Also, it's a German hotel. Should I expect any fees / taxes etc on top of the cert (or points), presuming I don't raid the larder?

Please help a clueless newbie out...first experience with using certs!

Thanks