I set up the BVM valve and servo, so when the valve is in full stroke / gear retracts, the servo still moves "over center" then pushes the button valve to close the doors. you do need to use servo speed in the TX to slow the servo down so that it gives time for the gear to come up before the button is pressed. this saves a sequencer / servo.
i have found the BVM valves top be pretty much bullet-proof.

Kirk