Today, I have started the retopology of the model. One interesting thing to do that I found in the tutorials was that, once you save the high poly model in Zbrush and imported it to Maya, save the high poly model as a GPU cache file. Then I could delete the high poly model and open the GPU Cache file, make it live to use the surface of the model as a snap magnet to use quad draw on it. I also used layers to have a quick access to the high and low poly models and have an easy and quick way to take a look of the resulting low poly model. Apart of quad draw I also used in some cases the rest of sculpting tools when I had problems with quad draw.