Reciprocal frame offseting multiple curves normal to surface

Hi Everyone,

I am having an issue here with the offseting multiple curves normal to a freeform surface. I have made a reciprocal pattern on a surface using Daniel Pikers GH example definition for Kangaroo. Rather than making it with rods, I am trying to make it with flat planes that interlock. My method at the moment is to apply the curves to one mesh, then offset the mesh, apply them to the offset mesh, then flatten, graft and loft the two lists of curves.

As you may be able to see from the attached file, the surfaces successfully loft for only a part of the structure, and go haywire at the beginning and end of the lists. Any suggestions for where I may be going wrong?

Cheers!