I think it might be broken--Unfortunately I wasn't able to carjack a car. Maybe I wasn't positioned correctly? The controls were extremely difficult to maneuver with, so it was hard to come at it from different angles.
Thanks for playing! Yes you are supposed to be next to either of the car's doors in order to be able to enter it but your comment about the controls is accurate. It became obvious when I saw someone trying to play the game live.
