Hi mrjynx, Alias has a "Curve on surface" entity that associates a curve to live on a surface where it can be in the middle of the surface rather than only at a trimmed edge of the surface.

The part where you write: "at this point seems to lay plane over top" - that doesn't look like a plane, it looks like a blend is being created between those 2 "Curve On Surface" entities.

You also wrote: "plane gives impression surface is blended, even tho geometry is still underneath" - that's because it is a blend, it's just a blend between 2 "Curve On Surface" curves in the middle of the surfaces rather than between border edges.


That Alias software is tremendously complex, one of the ways that MoI keeps things simple is by not having as many different kinds of objects, so in MoI the only kind of curve that is implicitly attached to a surface is an edge curve, so you need to blend between boundary edges in MoI and not between curves somewhere in the middle of surfaces like you show there.

Hope this helps explain what you are seeing there.

- Michael