Dear Michael, I would like to know whether it is possible in principle (in the future) to rig elements in MOI3D?

In Sketchup has long is available plug "SketchyPhysics", allows you to combine objects in a hierarchical and manipulate arrays.
Of course, I do not suggest doing a full animation, as it allows SketchyPhysics.

But sometimes you need something like this: http://www.youtube.com/watch?v=9vU2MMc-woM
or this: http://www.giantmonster.tv/giant/?p=364

I would be grateful for your answer, thank you!