Hallo BurrMan,

I wrote I used 123d for Fillets.

So in Moi you create the Solid Objekts and Union boolean together. Export to step

For the Baseform I used the Freeware Tool Autodesk 123d, because you can Fillet to a Super Blend. Export back to Moi.

Cut it to peaces, as you like.

The slices you can chamfer in Moi Fillet.