I have a mesh which has many UV maps and a lot of textures applied to it. Everything is in one material.
Is it possible to Create a final UV map And bake the textures together in one big image?
Hope it'll help you.
You can choose from UVMaps using "UV Map" node (under input in material node editor), or you can use "Atribute" node and connect vector output to texture and write UVMap name to it. Also check Texture Atlas which been develop for baking textures from multiple object to one. It create one object and don't change your original objects. Here you can easily make new UVMap for baking textures to it.