Hi swordmac -
frankmli is correct, a screenshot would be helpful. At least a listing of your installation directories as they exist on your computer. Going back to basics here, can you give us some generic information about your environment:
Where is Unreal Engine installed? (exact path)
Where is Visual Studio Ultimate 2013 installed? (exact path)
Which program was installed first?
What version of the Source build off of GitHub are you using?
Thank You
Eric Ketchum