Null Reference Exception when trying to open shader.

Hey, Shaderforge bugs out and just goes blank when I try to open quite a complicated shader I was working on the other day. I also get a couple of errors of 'NullReferenceException: Object reference not set to an instance of an object'. Not sure what to do as I cant open up the shader in the editor to see what's going on.


Shader on pastebin: http://pastebin.com/4ctYYt4k