Ok now when you make the high res model ... i mean when you make the model into Zbrsuh you must export:
1) High level detailed model
2) get the slider to lower level " 1 " and export the low poly
3) download Xnormal ( program for baking normal map)
4) then into the program load into " High mesh " the High level detailed model
- Into the low res poly mesh import the exported from Zbrush low poly mesh
5) go to baking options set the 2048x2048 or what you want this is good for high quality normal maps
6) after that hit generate normal map or what was named the button in the right
7) then go into Maya
8) import the low res mesh exported from Zbrush
9) place a shader blinn on that mesh
10) hit option for the shader
11) click on the checker near the bump map options
12) select "TANGENT SPACE" !!!!! very important it is set on bump map but you must set it to TANGENT SPACE it's just from the drop down arrow
13) select file - > load the normal map .targa file baked from Xnormal
14) hit enter
15) select from the render menu hardware render option
16) render it with hardware