Warning NurbsCurve.ByPoints operation failed


NurbsCurve.ByPoints operation failed.
NurbsCurves require at least 2 points for interpolation

The elements I selected were taken from C3D and constructed in Revit via a Metric Generic Model Adaptive family (+ dynamo script).

Tutorial concerns:
Vignette 03 Defining a structural system
Dynamo Tutorials Part III: Defining a Structural System

Do you perhaps have a solution to this problem?

Thanks in advance.

170717_Tunnel_Roof.dyn (25.1 KB)

Roof_Points_Target Right.xlsx (13.4 KB)
Roof_Points_Target Left.xlsx (13.4 KB)
170713_Tunnel_Roof Target Left.rfa (384 KB)
170717_Tunnel_Roof Target Right.rfa (440 KB)