Boundary surface and solid union problems when working with lunchbox 2d truss

Hi everyone, I’m trying to create a grasshopper file that produces crescent trusses using a top and bottom line. I’m utilising lunchbox’s 2d truss component to help with the linework and everything seems to be going fine up to the point where crvs are turned into surfaces using boundary surfaces, extruded and solid unioned together. I know there are often problems with solid union in grasshopper but I can’t work out for the life of me why this one would be problematic as it’s all falt extrusions with decent intersections. The boundary surfaces themselves if baked are also really weird and render to a surface that is outside the boundary lines but still shows a surface boundary within the boundary curves. I thought these problems might be about curve direction but honestly I’m very new to grasshopper and am just shooting in the dark. I know I always say this but if anyone has any suggestions or has seen something similar to this before any help would be really appreciated.truss problem.3dm (65.3 KB)

just releasised the gh file didn’t attachtrusses.gh (42.0 KB)