Thx
Another little question :)
What is the normal use of a volume made in a Polygonal Prog ---> transform in Nurbs --> import in MoI
(so some Nurbs surfaces :)
Select all / Separate / Select all / Boolean Union ?
(file 3dm linked: volume on the left is the "poly" transformed in Nurbs) on the right the operations line above )
Seems all vertical facetts don't weld in only one facett?

Ps Does exist in Moi an automatic function after an auto-trimming of several nurbs surfaces for delete all that not define a volume?

Coons and Gordon surfaces are implicit inside MoI or don't exist?
coons planes http://www.cs.technion.ac.il/~cs234325/Applets/applets/coons/html/index.html

Gordon surface generated by latitude curves and longitudes curves with for each one point commun with each other :)