How to make Cesium rendering customized geometry with different color per-vertex

I've made my own geometry and copied the shaders of the PerInstanceFlatColorAppearanceFS.glsl to use in my own appearance. My library can be found here... with examples.

One issue I'm working out now is that I'm having trouble integrating a worker in this "plug-in" set up I have (Therefore I can't generate the triangles asynchronously). I have an open question posted here...!msg%2Fcesium-dev%2FULxqzpaQ68s%2FFJBsisdfys0J#!topic/cesium-dev/ULxqzpaQ68s

about it.