Also the normal map. Make sure it has correct gamma (linear) and correct value ranges. Incorrect gamma will cause these kinds of errors. The thumbnail for the normal map looks way too bright. If you look at a histogram, the red and green channels should be 128-255, and blue should be very bright.
My first 3d game art. It's Master Jiraiya of the Naruto series. Maya-Zbrush-Photoshop-Xnormal-Marmoset Toolbag, 11k tris, 2k color, normal and specular maps.
You can use overlapping UV's but you want your light map channel (normally the 2nd UV slot) to be uniquely unwrapped. If you don't have a second UV channel created I think it copies your first, which might be the problem you're running into? You can create a second channel on your own or have UDK auto unwrap a 2nd channel…