Thanks Remco - see above, AMS 2 didn't like Oculus services running in background.
Worked - Danke Schoen!
Everything's worth trying. No this didn't stick, but thanks for suggestion. Curiously, just tried and the game works fine with Oculus Rift, so...
Can start in desktop mode, but VR goes immediately into black screen. Have re-installed game. Have taken trace options, but no file. Completely...
Separate names with a comma.
