It slowly moves by itself. It's not road vibration - it will move by itself when the trailer is stationary.
I should still get full gas flow no matter where the selector lever is pointing? I don't want to lean out any appliances and burn them out. I'm hoping it can wait until I can bring the trailer in to have bigger issues like the misaligned slide fixed all at once.
I think this trailer is cursed or I got a lemon. So far I've had to had the axles re-welded, brake failure, roof leak, slide alignment and small minor issues. I hope it's just "teething" problems and things will get better once the initial problems are solved.