the drivers door locks mechanicaly via the door lock, once you turn the key 45 degrees and remove the key it physically blocks the lock from being opened from inside the car,the other doors are deadlocked electrically via the microswitch you have pictured,the deadlocks are closed by the drivers lock pressing and holding down the deadlock microswitch and opening when it is released,you should not be able to open any door from inside when the drivers door lock is in the horizontal position.
hope this clears things up a little,if not its cause ive been at the buds again and for this i apologise
