Grasshopper does not bake the same geometry as it previews

Hello everyone,

I was modelling a spiral staircase using VisualARQ in Grasshopper. When tried to bake it in Rhino it did not bake the same geometry as the one previewing in Grasshopper (you could see the difference in the images attached below). I was reading about similar scenarios in the forums where invalid geometry appears to be the reason for that but I am still struggling to solve the problem as the only geometry I am using in Rhino is a simple curve. I would really appreciate if you could help me to figure out how to find solution to that.

Thanks in advance! (6.2 KB)