Hey, Gerhardt, don't give up - the game's worth it! Music after the shout "Clear!" is still normal, takes a while to load. If you're on a German system, you must make sure, that ALL regional language settings are set to "English (USA)". And you can't type in any pilots with German letters like "Ö" or "ß".
My wingman and neighbour had success at last, after a long time of attempts, by pressing "Manual Install" in the "Workshop" menue. After a short install time, suddenly, the game worked. Perhaps you try that. There's also a "CFS3 Config" button, but I don't know, if that helps. I'd try it though, before not getting anywhere.
Cheers; Olham