Gonna go ahead 6 months in my time travel machine: landing gear.
As I recall on Bob's videos, at BITW and other places, pneunatic gear was just not up for the task. I see the nose gear has two actuators.....perhaps it was a mod after the fact.
I sincerely think pneumatic is a no-go for a model this size. Saw Bob's citation gear and off the bat did not see any locking mechanisms on his sketches. Not sure if the same is true for this one. Now, rather than sending to down n lock or similar, I'd just go to servocity and get creative, but I think a good screw jack drive should do the trick (torque is so high on those!).
If I can be of help with sketckes or ideas let me know.
awesome build!
David