Shaders on the second UV channel

I’m doing a little experiment, and I’m wondering if it’s possible to create a material for the second UV channel.
I’ve created a few baked light passes in Maya and wanted to bring them over to UE4.

This also ties to the question of where does UE4 store the lightmaps and if you can edit them in the material editor.

You can choose which UV to use, using the UV Coordinate node.

Thanks man!
Cheers