At the end, and after spending so much time looking at tutorial after tutorial, I decided to just edit one big mesh and make it look as good as possible with a tileable texture. much more easier as Zbrush does the complicated UV mapping for you and it's really easy to export back to Maya once you set it up. After running a decimation to avoid killing Maya on the attempt to export an object with over 1 billion polygons, I got quite surprise that it changed from quads to triangles... never worked with them and my previous 3D professors where completely against working with them.
Didn't care...
So manage to get the normals working and to get it all fit and scale with the rest of the scene. So far is the object that's spending most of my poly-budget, but hopefully will be worth it.
I still want to play more with Zbrush, since it's a really different software, that quite took me a while to get my head around, but seems like one of those in which I can see myself getting lost for hours just trying and trying all the tools.
After duplicating the half of the cenote (cave) on which I worked on, and merging them together I saved and closed Maya, but is until now that I noticed that by doing that I completely destroyed the UV map and it was turned into a square, so now I either work with an automatic UV proyection or start working on a uv mapping of an object that has over 67,000 polys and loads and loads of organic bumps. God save my soul if I chose the second option. (which I probably will)