Unreal 4.20.3 Not working with HTC Vive

Hi Everyone,

 I'm working with 4.20 to write a book about getting started with VR. After installing 4.20.3, the HMD is no longer working Unreal despite SteamVR saying everything is fine. When I hit play to preview my game I see nothing but the generic white plane in the HMD and the camera in game does not track with the HMD at all. If I go back to one of my VR projects in 4.19 everything works fine. Everything also tracks fine in SteamVR Home.

Anyone else experiencing this? Anyone have a solution? I have deadlines and this is not helping.