Rear passenger door can't be opened

[jackshaft]

My rear passenger door cannot be opened with either the inside or outside door handles (nor the central locking). I've tried the basics, disconnecting the battery and checking the wiring for breakage, with no luck and have come to the conclusion that I need to replace the lock. To do this, I need to somehow remove the inner panel and have managed to unscrew the lower torx screw and the two screws in the panel handle. But before I attempt to remove the panel, I'd be grateful if anyone has any tips how I can set about removing it to minimise or hopefully avoid damage. For example, is it possible to start at the top with the window down?

Many thanks, Jack