Solution of my problems found
Because the thread was closed, I am sort of forced to start this as a new topic which seems a bit odd. However, I did feel it might be of value to know what caused my problems. These were:
1. Computer demands driver when I connect USB cable from player
2. Player doeasn't see it's own factory mounted and formatted 2 Tb Harddisk
3. A horrible sound quality both from films played via USB stick and from internet sources
4. No properly functioning network as seen by the PC.
I got the advice that the box may be faulty, it went to Rotterdam but came back as it was.
Then I went with it to Rotterdam, only to witness that there it worked OK
Back home the same problems. I went to the home of friends and there too the same problems.
Solution: as it appears the power supply was malfunctioning. It did work but somehow not good enough to make the four points mentioned above work properly. At acryan most likely their own power supply has been connected so they saw nothing wrong. I never thought of that before because the box seemed to start up normally.
Glad this nightmare is resolved!