Test with the free Vizcom :)
Screen shot of the Moi3D object
Input Image
Then Render with a reference image to control the style and textures in your renderings.
So, what's you're specific process for constructing these "fillets"? How do you trim the adjoining surfaces to define the extent of the fillet? Are you using Construct > Blend to generate the fillet surfaces, or something else?
It looks like you're avoiding solid operations, like booleans, entirely and I'm curious why.