I like a sequencer and the one I have used the most is the RCBee sequencer. It has a warning to protect against switching on and inadvertantly raising the gear. It has 2 modes, one for normal doors open gear down and staying open till gear up or, gear down doors close and doors open before gear is down. There is a variable delay. It is simple cheap and works well. It saves a channel as you only need one for the gear and doors. I tried with using micro switches etc but this is far better. I prefer several electronic valves rather than one all in one. I like the Jetronic valves with the air save facility.

John