You might be better asking here : https://forum.dynamobim.com/ That's where all the Dynamo gurus tend to post, you're more likely to get an answer there. You might need to flesh our your question a little as well though but there are a lot of threads already relating to Nurbs curves.
"Give a man a fish and you feed him for a day; teach a man to fish and you feed him for a lifetime."
Maimonides
