sorry mate...busy last day at work yyyaaaaaayyyyyy. Ok as Oz said if you hit that little blue icon it will show you overlap and 'flipped' UV...ones whos faces are reversed in the model...I found this when doing my spitfire tutorial...as ctbram has said turn 2 sided lighting off when you model, you can then easily spot the reversed faces.

As for the UV's Oz spotted they are either underneath or on top of the others, just simply spread out the UV's on these two sections a bit more, hitting the UV colour icon will help you mate.

cheers bullet