I have been using MoI and Keyshot together for a couple years. To render a MoI file in Keyshot, what I do is first create and save a MoI .3dm file. Then I save that file as a Keyshot .obj file, selecting the "quads and triangles" option in the MoI popup menu. Then I open Keyshot, and drag and drop the .obj file. When I drag and drop, an "import" popup window opens in Keyshot, and in the "Materials" section I always check the box that says "Keep individual parts" and on the drop-down menu in that same section of the popup, I select "Group by "Materials"." When I follow these steps exactly, I never have any problems.

Here is are images of some recent furniture designs...from my imagination, to MoI, to Keyshot: