Hey Rybam. I just figured out how to get it to work! When you place a driver seat and the treads are connected to the tank engine and the tank engine is connected to the seat. You need to place two buttons on the creation, paint one of them black and the other white (I used the buttons from the mod), then connect these buttons directly to the tank engine (all other connections are left alone) and for each button press for the white button the engine speed will be faster and for the black button the engine speed will be slower. I gave up on the treads for a long time myself and I am now going to be making tanks for the first time ever in this game. Hope this helps ya out.