SteamVR: Custom Loading Scenes

How can I implement / set custom loading scenes with SteamVR?

Like they did with “The Lab”? Is there functionality in UE4 already for this?

I believe the key is to use level streaming. Here is one explanation of the process.

I’m not talking about just any loading screen.

In SteamVR there is this white room that fades in every time you start/stop a VR program. It even fades in when UE4 loads a new map (with “open level” for example). This white room is what I want to change and customize.

It must be possible, because Valve does it in “The Lab” and I heard “Hover Junkers” does it too (couldn’t try HJ yet).

Oh, how interesting! I have never used any VR myself. I hope someone knows the answer and enlightens us.