Don't try to bake normal maps with Zmapper ... it just can get a good normal map or just don't work for me fine ... Download Xnormal and read the manual. Make the normal map with Xnormal just my XP shows that Xnormal bakes normal map perfect for Maya to use it. If you bake a normal map from Zbrush sometimes you need to flip the green channel because in Maya that channel is flipped compared to Zbrush. But 1st read and learn how to UV layout !!!!! VERY IMPORTANT !