Problem making a surface from Points Grasshopper

Hi! I’m Having trouble getting this to work, So I have some countour lines from wich I want to obtain a Surface, I already tried using a mesh to work but It’s not good since I can’t make splits or other operations. I was following this tutorial but the problem is that my countour lines don’t fit on a square so I’m trying to get a workaround to get this to work, I’ll attach my files for the model and the (44.1 KB) TERRENO LIMPIO.3dm (13.9 MB) HOPE YOU CAN HELP ME!!