Conceit: Thanks! So, I am controlling the ramps directly. Here's the texture.

The way the shader works is that it only lets you set the vertical (v) position of the UV map - the horizontal position is skewed side to side based on the angle of the surface to the scene light, the in/out shadow value, and vertex ambient occlusion.
You can see in that map that there's some hueshifting going on - not a huge amount, but some.
If you're looking at the build (or those images I posted) the palette being used isn't exactly accurate. I've added options to palettize to classic videogames. The examples I posted are being indexed to Rise of The Triad, Arne's 64 color palette, and Duke Nukem 3d. The only one using the actual palette I made for this project is the image on the light background with no AA.
http://www.hedfiles.net/PixelShader/pixart_01.png
The difference from the IRKALLA mechs is that those were pre-rendered in Max, using a procedural max material. This is 100% realtime, designed for use in games.

lachrymose: Thanks! This actually works on everything, including phones and tablets.

I don't know if it's just me but all I see it's a pixelated image