Sorry I can't help you with the unwrapping, I still didn't learn that in maya. Anyway: i was wrong with the diffuse map (that's how it's called in the other software I use)..in Maya it's just called "Color" and it's basically just the colors and paintings on your object (in my test it would be the white material with the dark stripes and text + scratches). To apply it just selec the object, apply a material, click on the little arrow near the "Color" in the material tab and select "File" then browse for your file and it's done.
The Bump map simulates depth in your object without adding geometry to it. Here it's explained better:
To apply it do as you did for the color, just click on the arrow near "Bump" instead of "Color".
Whe you paint your textures remember to remove the white painting near the hard edges, just like the example robot you showed!