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... https://github.com/brianolsen87/cesium-plugins 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...

https://groups.google.com/forum/embed/?place=forum/cesium-dev&showsearch=true&showpopout=true&hideforumtitle=true&fragments=true&parenturl=http%3A%2F%2Fcesiumjs.org%2Fforum.html%23!msg%2Fcesium-dev%2FULxqzpaQ68s%2FFJBsisdfys0J#!topic/cesium-dev/ULxqzpaQ68s

about it.