Kurzer Nachtrag:
Die "komprimierte Form" ist wohl das "Wallet Import Format".
Dieses bräuchte ich im "Normalformat".
Wie wandelt man das um?

Habe diese Info gerade gefunden:

A compressed address is just the way of storing a public key in fewer bytes (33 instead of 65). There are no compatibility or security issues because they are precisely the same keys, just stored in a different way. The original Bitcoin software didn't use compressed keys only because their use was no disadvantages other than that a little bit of additional computation is needed to validate a signature.

Danke!
Alio33