Right now on my home system i have downloads a variety of custom forge maps. I put all of those forge maps on a usb so that i could play them at a friends house but for some reason the game would not pick up the maps. Is their a file that i am missing because i copied over the entire halo 4 file but it would still not let me use those maps on a friends xbox.
Your profile will need to be on that USB and signed in for the Forge maps to show up.