The inner arm/hand part broke off my Hyperdrive. The inner arm/hand is strongly tabbed into the roof part of the car (just below the side window) and the door panel is attached by a peg to the inner arm. So if you pull out the arm by using the panel, instead of by the hand, the inner arm/hand can be left behind still tabbed in and the peg snapped. It's the same design on Blackjack and similar moulds (Roadhandler, Swindler and I think other cars).

So a word of advice - pull the arm out using the hand not just the door.