I can get it to work with a simple new test project and can switch forward rendering on/off via console without problems. Starting in standalone game play mode from editor.
When I try it with an existing project (based on “Landscape Mountains”) it will crash right after starting as standalone game from editor (forward rendering was not turned on at that point).
[2016.06.01-12.22.48:681] 2]LogWindows:Error: === Critical error: ===
Assertion failed: (GIsCriticalError || !NumMarks) [File:E:\UE4\src\4.11-ofr\UnrealEngine\Engine\Source\Runtime\Core\Public\Misc\MemStack.h] [Line: 90]
Play in viewport seems to be working, but only if I have the HTC Vive disconnected. It will still crash when turning forward rendering off after it was on.
Was anyone able to get the forward renderer to work with “Landscape Mountains” (and HTC Vive headset) or do you also experience these crashes?