Vertex Offset Particles Issue

While using the spherical world technique I encountered a problem. Everything works as expected up until I try using the shader with a particle system. In the example I use the same material and shader on both the scene objects and the particle system.

As you can see, the particle system should follow the curvature and keep a proper position in world space as it does in the hand written coded version. When using the Shader Forge version, the particle system is nowhere near where it should be, if I were to zoom in the particles would completely disappear into the distance. Any idea what is going wrong in this shader tree?

Note: The code example image is not from SF, it is the hand coded version in which particles follow correctly.