I slightly scaled them either in the U or V direction to fill up space. Regarding your AO bake errors: * Make sure the Cage encompasses the entire HP and LP * Make sure you have "Closest hit if ray fails" unchecked within baking options and "Ignore backface hits" unchecked as well within AO settings plus uncheck "limit ray…
So, this can get a bit more complex than you probably need at the moment. I will explain some basics and a bit more... advanced I suppose. Most if not all objects in a game will have two UV sets. What are these UV sets?* UV set one = This is your diffuse map/albedo map UVs. Here all the UVs that will display your textures…