The vibration is more than likely a drive shaft. Get a quality replacement for the 130. I fitted cheap ones, Q something, on mine and they were rubbish. Fortunately got a refund. The remote key may need reprogramming to the car. I think there is a link in the FAQs at the top of the forum on how to do this. Electrical issues are normally due to wires breaking and shorting in the gaiter between the car and door. Start checking with the driver's door first and work your way to the least used door. Also check in the gaiter on the tailgate. This could be the cause of the door mirror not working and, believe it or not, your radio not working all the time. Not sure where you can source a key for the tow bar but try a local locksmith. As far as I know the wiring is modular and I think connects in the offside rear light.