Go to Tool > Masking. You have many options here too, but you need the Occlusion intensity slider and the Mask Ambient Occlusion button. Get the slider to 5-6.5 or so. Higher values take a longer time to compute but give deeper occlusion. Wait a bit and then press Mask Ambient Occlusion and you should see what is shown in Fig.15b. Go back to the Texture Map tab and this time click Masking > New (Fig.15c). Repeat the steps again, clone your map then go to the Texture tab and export it. In Masking Tab there is a Mask by Cavity option. You can press it and generate a cavity mask. Then go back to Texture Map > Masking > New and you can get a nice cavity mask too beside the occlusion one. But this is an option you should only use if you want more details in your texture after combining all maps in Photoshop.
Fig.15b & Fig.15c
Well the maps are ready now and you can combine them in Photoshop. Separate them from the background first, then use the color map as foundation and the occlusion map on top of it but, with Multiply set as the layer mode. If it is too dark then reduce the opacity a bit. Also as the layers are set on multiply then you can add the cavity map here if you have one. I also added a real stone texture but with lower intensity to enhance the map details. Finally you should have something similar to Fig.16. This image also shows the normal map previously generated in 3ds Max and a render of the model in Max with the normal and texture maps assigned.