Damn it! I got it.
Never mind.
Maybe this helps others to get to the point quicker than I did:
The private key, which is needed to connect to the Gateway (Option 1 in Paper UI for the KM200) needs to be generated.
You can do this here:
https://ssl-account.com/km200.andreashahn.info/
Two things are needed:
- You need the gateway password or Geräte Password (on the Km200 sticker, but without the “-”).
- The personal password or Benutzer Passwort you’ve set up using the App for the first connection (e.g. iOS App from Buderus).
The generated key is the one you need to put into Option 1 at Paper UI.
After that the connection should be done.