I've been interested in MoI for a while and got around to installing and playing around with the trial version. I can see how the UI is designed to work well with a pen, I was able to run it on my Surface 3 and the pen interface seems quite nice. It is a bit sluggish on the Surface 3 (non-pro) but still usable.

My interests are along the lines of being able to extend MoI. I see that you can write JavaScript + HTML to add new commands and even some simple user interfaces. Is it possible to write extensions in other languages? The IDL file looks like it is COM, can I do out-of-proc COM automation to add my own features? Or is it possible to have JavaScript call code written in another language? I've not played around with what is possible beyond downloading and looking at a few sample extensions.

The license agreement for the trial prohibits reverse engineering or modifying the program. Does the purchased version contain the some prohibition? I couldn't find a link to the purchased version's license agreement. As many of the commands are JavaScript + HTML, i'm wondering if I am allowed to tweak them as I need, or if that is verboten. I get that it wouldn't be supported and could be lost with upgrades, I'm more wondering if it would be allowed / legal or not.

Regardless of these answers, i'm betting i'll end up buying it. I've done some 3d printing work with polygonal modelers and was frustrated that their booleans mess everything up. Booleans are so useful for thinking about the design of an object; they need to be a primary tool rather than a last resort. So NURBS and solid geometry seems a good match for what I need and I am impressed at how easy MoI is to learn and what can be done with only a few commands.