Hi there, no, i won't write "I got the solution, thanks, bye".

The problem was that the activeX wasn't completly
initialized, in which way ever the show method of the
form called the EndInit() Method of the ActiveX and made
the usage afterwards possible.

Solution: Just call it yourself.
Form myForm = new Form();
AxMappointControl mapPoint = new AxMappointControl();
myForm.Controls.Add(mapPoint);
mapPoint.EndInit(); // <- That's the way
mapPoint.NewMap(MapPoint.GeoMapRegion.geoMapEurope );
myForm.Show();

Sry for my bad and irritating english, i'm german an not quite
used to write or talk in english. Hope this helps some of you.