Creating a sphere with indents with Kangaroo

Hi all

I am trying to create a set of spheres with a set of points across the surface. I am attempting to use the points to pull the surface down at these points. I assume that I need to use kangaroo. I have set up a unary force. I cannot for the life of me work out what I need to do to get the points to pull. some advice would be appreciated.

please see attached sketch of what I want to do and my Grasshopper script (451.4 KB)

Sent it to you earlier mate, sort out the null points issue.

Kangaroo simulation - Henry surface pull (372.8 KB)