Hi Matadem,

So on this one the problem is that you've got 2 curves selected there so it's doing a curve blend. To do a surface blend you need to have 2 edges selected, not 2 "standalone" curves.

The curves there are stacked up right in the same location as the edges and that will make the edges difficult to get at. Try selecting the curves and using Edit > Hide to hide them, or delete them so they will be cleared out and won't interfere with selecting the edge.

Re: Flip command - that doesn't really affect operations in MoI itself but it will do something in polygon mesh data that is exported out from MoI to a rendering program. If you use the Flip command on an open surface, the face normals in the mesh object will be reversed.

- Michael