<shameless plug> Load your normals in CrazyBump, and render shadows with the sharpen slider around 95. Copy the output into Photoshop and paint over it! </shameless plug> edit: I guess my shameless plug was unnecessary. MoP beat me to it
I always use an AO map on top of any local map generated from high-poly geometry. In Max I always bake different "material" sections as different colours like EarthQuake said - as contrasting as possible so you can use them as selections in PS. Just assign different materials with different diffuse colours then add a…