Another thing you might check is TopMod: http://www.topmod3d.org/

I believe it can open and save OBJ files, and it has some kinds of polygon subdivision tools in it which could possibly help to generate the variant you want. Possibly the forum over there may be a good place to ask about that particular variant.

Then you probably already know this, but just in case - if you want to get something that is in OBJ format back into MoI, you can use this wireframe converter:
http://moi3d.com/wiki/Resources#Obj23dmWireframe_converter then pick lines to make up a plane and fill it in with a Construct/Planar.

- Michael