Hi my team is working on Unreal with Plugin version 1.20(for UE4.20), and posting this to share our issue.
During the early stage of runtime, the log is saying that "OCULUSHMD_OPTITRACK: Sensor fusion failed to initialize.", and rendering just one frame of random screen on HMD.
Based on the source of OculusHMD.cpp, I was suspecting that the result of NaturalPointHmd_ValidateAuthentcationToken(Line 359 of OculusHMD.cpp) from DLL is giving false.
And one more strange thing is that there is significant time different between "OCULUSHMD_OPTITRACK: Initializing sensor fusion." and "OCULUSHMD_OPTITRACK: Sensor fusion failed to initialize.", which is about 2 seconds. So I do not think it is properly set, but I want to ask what is the condition to NaturalPointHmd_ValidateAuthentcationToken to be true to get the clue about.