ZBrushCentral

Zbrush 2 Mixamo Issues

Hello,
I am currently having problems when trying to get the right finished product out of my Mixamo exports and I think the underlying issue is how I am setting my fbx up in Zbrush. I have a cartoon style character consisting of 6 subtools each subtool was uv unwrapped and then the texture was applied via create new from poly paint. When he is exported out as a fbx and then uploaded to mixamo, everything seems fine. He is showing full color in the Mixamo viewer and animations work fine. When he is re exported and then put into Unity he is grey again and all the subtools are gone and just showing the mixamo skins that come with it… Through reading other forums someone said the problem is fixed via baking your textures. I dont really understand what process that it. It seems you have to use photoshop or other programs to get that to work. Why is that necesary when he was already polypainted and looks fine. Also if I import the original fbx export into Unity without going into Mixamo he looks fine and all the textures are there.
Newb looking for help:o