I am setting the layout using the following code but evertime the graph is rendered it renders in a random order, the nodes are placed in different locations evertime. Help? Thanks in advance!!!

var layout = new NSpringLayout();

var shapesToLayout = drawingView.Document.ActiveLayer.Children( NFilters.Shape2D );

layout.Layout( shapesToLayout, new NDrawingLayoutContext( drawingView.Document ) );

drawingView.Document.SizeToContent();

The force directed layouts (the spring layout you are using is one of them) are non-deterministic layouts, i.e. they may produce different results even when applied on the same input graph. If you want a deterministic layout try one of the others (e.g. Layered Graph Layout, Radial Layout, Orthogonal Layout, etc.).