Alright, it worked now.
You have to click the paypal button ^^
Seems to be a bug, because the paypal option at the buttom doesn't work,
if you don't use the paypal button and log in into your paypal account.

To bad, it says, that the key is coming in 1 or 2 days ;-)
Thought with Paypal it will be faster.

Can't wait to start again with A8.
Not the best engine, but a german community and easy to learn. ^^