Well, I got it work :)
I don't know exactly what I did, maybe I got the STAR and TRANS right this time!
As soon as the right ILS frequency is automatically entered in the tuner in the first place, it will smoothly follow the glideslope down to the RWY.

But for some reason it landed approx. 50 meters to the right parallel to the RWY? Is this a bug in FSX?

Best Regards and thank you again for the advice,
Anders