Mesh Surface not working???

Hi all. I have been trying to make my grasshopper model ready for karamba analysis but since i´m very new both to GH and Karamba I need help! If you put a insert a single point into Rhino and then assign it to the point in the grasshopper script you will see my model. What I am trying to do is to use this model for stress analysis in Karamba and for it to work I need all sides of this geometry to trianglulate correctly. Jet the cap on top and at the bottom dose not trianglute correctly and I hope someone kind hearted can tell me why?

If I'm not making sense please ask me.

Kind regards, Ragnar.