Sweep ellipse along a fancy curve with variable section

Grasshopper Developer
1

Hi guys.

I wanna achieve in Grasshopper the same result as in the attached Rhino file. Sweep one rail does not work for that, extrude along as well. Loft, neither. Apart from that I can’t understand how Heteroptera’s Variable sweep works, but anyway, it’s probably not the right solution.

ring 05.3dm (2.3 MB)
ring 05.gh (54.2 KB)
ring%2005

I’m working with Rhino 5 and Grasshopper version 0.9.0076, so I would be grateful for a compatible file, if possible

Thanks in advance for any help.

Cheers,

Benoit