Filehandler do not show up

[IWreckedIt]

Hi,
I tried to run this sample to get a custom filehandler in sharepoint online. I can login and the demo page shows up, but whatever I try and after waiting for days (48h delay...), I do not get any handlers in OneDrive/Sharepoint.
Is my understanding correct, that the mere registration of the manifest in the Azure portal is basically sufficient to start this "distribution" of the handlers to sharepoint? What could be wrong, what might be missing here? Are there any debug option to get some more information?

I also tried to call the reset cache method to clear the server cache as described in the ms documentation, but I am not able to succesfully perform this post action. (Token type invalid)

Any help or ideas are wellcome