A baffling issue with coloring lines.

I have a sophisticated curve rendering that uses basic line segments in an animation capacity. I tapped into the Camera.onPoserRender(...) callback to manually draw. Attached are the shader, line drawing and constructor source in question. I am using a single class called UnityGraphicsCanvas that acts as the graphics proxy. With all respect, please do not ask "why" I am doing things this way, it is based on scientific research from a visualization analysis project translated to Unity. I am no novice to graphics development and have tried every permutation of materials, lighting direction, attenuation, etc., but no matter what I do, lines will not color and are always white. Perhaps I am overlooking a simple setting?

It might help to know this code is being transferred from a functional XnA graphics environment to the UnityGL graphics environment. (There is no XnA code referenced anywhere).

Thanks so much in advance.