Hi Ralf,
I can only answer one of your questions; I am (also) a user of the Expansion pack, and its updates come hassle free: because it is installed as a plugin, whenever there’s an update for it, the plugin’s page will say so, and you can update through there (:
I hope someone will help you with your second query, for I’m afraid I have no knowledge about it…
Greets,
Kiyo