This button doesnt work on mine! I set up the controls and nothing happend too. Is it some version issue? Cause mine is 5.1 Btw, is 5.1 too outdated?
You won't get any support for older versions, update your game (or rather, buy it). Then we may be able to help you.
5.1? You maybe meant 0.5.0.1 That's too old, that feature wasn't existing back then IIRC. Update your copy, from the store you purchased it from:https://wiki.beamng.com/Updating_the_game