Mmm I don't understand very well , but if I think I do, all my makemdl planes the gears dissapear once the finish the complete the retract
this is an example of the Citation X center gear (Ignore the spanish stuff I used this shot to teach a Spanish Guy)

It didn't close all once they're were up because the space were too strech it if I would it animate it completly I would have to see the top to the tire in front of the nose , but this goes to all gear in makemdl9 I think is not part is just the way they did ,once they up ,they dissapear
is not the same case with FSX-SDK
Alex