Dynamo - Robot: creating surfaces

I’m trying to create a discrete surface in Dynamo whose final destination is Autodesk Robot Structural Analysis (RSA).
This shape is just a ring for which I have created a profile (simple vertical line) and a path (curve - circle) and used Surface.BySweep.
The issue is that when I import the surface into RSA using AnalyticalPanel.BySurface (and 40 divisions) the programme does not show the surface as a ring but does sth not desired joining points between the two limit circles of the ring.

I understand I might have to do sth with the surface beforehand, any help highly appreciated.

Try splitting the surface into two discrete semi-surfaces - by breaking both curves at 0 and 180 degrees and see if that fixes things. Full circles of any kind are often a pain point.