Realy thanks a lot, that explains the case very good.
I couldn´t understand why the selected models in the app work so fine, and the standard models gave problems.
It´s still some of a mystery though, that for a period ( around two weeks ago) a little trick could make our own models perform fairly well from the webbrowser, now this feature is of, the site reloads when I try to view my own models from the webbrowser.
(The trick was to Request Desktop Mode, and then it performed quite well.)
The standard web-version also performed perfect on the PC-based Oculus Rift, also with the Oculus Rift controller which could be used to navigate in the scene.
The Oculus Go controller works in the VR app, but not in the standard web-version.