Using Starnet Preanalysis

In expanding my control network across 25 acres of hilly, fairly densely wooded terrain, I've attempted to create a lattice of triangles (Arc of India style).
But in some places, it'd just be too hard to cut the lines I'd like, so have opted for a number of rectangles.
I sense that, because of the additional observations, the relative uncertainty of the location of a point traversed via a "diamond" vs a triangle, might be greater. But how much greater?

I'm trying to use Starnet's Preanalysis feature to find out, but am getting lost on how to set it up.

Here's the plot. Ideas appreciated.