selecting items

Hi all,

I am pretty new to GH and I was trying to model something, more or less try out. I made planes on the normals of a surface. I used item compound to select the group of planes I wanted. From those selected planes I want to select different ones. I used cull pattern and cull N compounds but they dont function. Plus to that when I use cull pattern on a divide surface it chooses them as z-axis based stripes but I dont want stripes.

I tried to explode tree compound which also didnt help much. What should I do in order to select some of the planes on my surface? Or in general how do I choose some data from an Item compound?

I dont know if it is important to know but I work on Bootcamp, Rhino5, GH 0.9.0014

Thank you for your help