Workflow 3ds Max - Unreal - Oculus Quest

Hi, I'm new to developing for the Quest and I'm running into some issues. I've build a scene in 3ds Max 2016, exported it with Datasmith to Unreal 4.21 and from there into the Quest. I followed all the steps from the quick guide and other tutorials and the first time everything was good, except the textures (Vray Next). So I changed the textures to some nice ones from Substance without knowing that Substance isn't working, too and there are also issues with Quixel Materials. Lastly I changed all materials to very simple ones to have a first look WITH materials in the Quest. But with all these changes done the project doesn't start any more in the Quest. I see only a black screen and the project closes itself after a few seconds.

Is there any guide or documented workflow how to get such a project into the Quest? Or do you have any idea why it shows a black screen now?