Well. steam doesn't provide pad option for this game I think. I used gamepad for OGR steam version. The program I used is called X-padder. With this you can manage almost every kind of key mapping including vibration(This part I really liked) easily.
It was quite difficult for me to play OGR with pads so I quit, but you should look into it. (Not a free software though. It is free as far as I know. if you really want to use gamepads, I think it will worth trying.