List Control For Infiltration Basin Calulator

Hey Guys and Girls,

I have (almost) create a basin infiltration calculator. It creates hatches based on the infiltration polylines and basin polylines. (Convert them to surfaces, the compares the surfaces, and then (should) make hatched based on the infiltration layers). Can I get some help on the last remaining items I can’t figure out.

#1)Layer.Create seems to only work sometimes. Other times it plots to layer “0” which is weird.

#2)Layer.Create doesn’t work if the layer is already created. I got a filtebyboolmask to determine if the layer is made or not but need to merge the two list after.

I need some help with the list control. It seems to only do the first polycurve in the list. How can I repeat it for all the polycurves?

Basin Area_v3.dyn (293.6 KB)
Final Drainage Impervious Exhibit.dwg (6.5 MB)