List insert avoiding repetition

Hi I have imported a cad file dwg into Rhino.

Attempting to make 2d to 3d

I have created a polyline(s) from a collection of points to represent a abutments, north and south.

I have captured some curves, transformed them, and lofted between the curves. I have repeated this 3 times.

When i create a list to avoid the repetition, something funky happens with the lofting.

Can I have some advice on how to order the list to avoid the repetition. ie the move . Creating the list input to avoid 3x move commands

Many thanks

Screenshot shows the polylines for the curve containers.

  • screenshot of curves

  • rhino geometry from dwg

  • grasshopper definition

Superstructure_Rev_A.3dm (891.9 KB) (9.3 KB)

Screenshot.pdf (149.5 KB)

You can graph them (6.5 KB)