This probably won't be easy to add anytime soon, because MoI's tools are focused on smooth NURBS surfaces.

3ds files only contain faceted polygon mesh objects, where each object is made out of a bunch of little triangles instead of being made up of smooth surface patches.

So that's kind of a conflict between the way that objects are stored. MoI can export to .3ds by taking the smooth surfaces and breaking them up into triangles. But it is very difficult to go in the reverse direction.

- Michael