In the Overall diffuse coloration, I put the diffuse map created in photoshop before and hit render again to see what is going on.
After that I worked on the environment, adding small rocks, grass, and bush's. All was modelled using simple poly shapes, duplicating and scattering all over the scene.
I added some more spots and omni lights in the scene. With all the lights setup in the scene it was time to add the Global Illumination effect. On the rendering panel, in Indirect Illumination tab, I turned on the Final Gather, lower the samples, turned on Preview No Precalculation(for fast preview) and hit render. The rendering process became much longer.
I've played with the samples number for Final Gather trying to get the best result and optimal rendering time. For the final image I've rendered different passes and imported them in photo shop. This technique allows you to have more flexibility in compositing later.
Here are some of the main passes.
I used photoshop for doing some tiny color corrections. Here is the final image
Hope I've been as clear as possible, explaining the way for creating this image. Thank you for the care and patience.