Extrusion height based on color in a gradient, shadows casting on curved surfaces.

Please help.

I used a sun path definition to cast sunlight onto the geometry, where the most intense light is a shade of red that fades from yellow to blue as the light looses intensity. 

There are two problems with the definition I have now:

1- Shadows do not cast onto the object its self, or other objects around it.

2- I need to apply a rib-like pattern to the existing geometry where the extrusion height of the ridges corresponds to the intensity of the light (the closer to red, the higher the extrusion).

The result would look similar to the Aqua Tower, where the overall width and height can be adjusted relative to the intensity of the light.

I have python, weaverbird, galapagos, ladybug, and human plugins - I can add new plugins if necessary. 

Any help you can give me would be greatly appreciated.