Since the 0.26 update I think I can safely say all 'motionSim.lua' plug-ins have to be updated to work and this time also with SpaceMonkey. I did a complete wipe, but once the Sim Commander plug-in overwrites the 'motionSim.lua' in \Program Files (x86)\Steam\steamapps\common\BeamNG.drive\lua\vehicle the game literally puts you under the tarmac and stops working and with the SpaceMonkey plugin it just don't work.
And if you think that BeamNG is just a niche-title: Still over 12k average players, so more popular than iRacing, F1, ACC etc...