Revit Families - Referencing Model Elements for Loft

Good Morning-
Looking to create a series of vertical, rectilinear tubes along two Revit splines.
I’ve had success lofting lines/cylindrical tubes using two flat splines, modeled right in revit (no change in z direction).
It seems to have a problem when I select my more complex Revit family, which consists of a simple spline though points. The points have various x,y and z components.

I was using Select Model Element- to Cure Element.Curve.
Any help would be greatly appreciated. Thanks!Capture

Good Morning-

Still struggling with the the same issues.
I’ve attached an image below of what it is I am trying to achieve. The tubes in the below image were created with Rhino + Grasshopper. We are looking to recreate this script in Revit; but with the flexibility to make the fins more regular in nature / fixed directions.

Any thoughts?
Thanks very much.