Surface From Mesh (or nurbs in this case)

In this definition I'm trying to create a roof structure that mimics the approach of the Great Court roof of the British Museum.

As you can see in the file attached, I'm trying to change the geometry of the mesh I created with Kangaroo into a surface in order to create surface subdivisions that will functionally serve as the triangulated steel grid that will hold the surface (mesh, originally). I was able to define the nurbs from the kangaroo mesh, but I couldn't create a surface geometry. 

All steps in the file are annotated. 

Any help or guidance would be greatly appreciated!