Building texture

I am thinking about creating blue cave paintings on the wall of the building by using composite map function in 3d max.

Reference image:

http://ngm.nationalgeographic.com/ngm/0508/feature2/
http://www.antbear.de/bushman-rock-art.htm
http://www-personal.umich.edu/~bclee/rockart/rawallpaper.html
http://www.historyforkids.org/learn/africa/art/san.htm


The image I created:

On the second thought, 3ds max composite map function DOES NOT work in Unity. So I don't think I can implement it using composite map.