Things You'll Need
Instructions
Connect the USB flash drive to your Xbox 360. Turn on the system and open the System Settings screen.
Navigate to Storage, and then Hard Drive. Select ̶0;Minecraft: Xbox 360 Edition̶1; followed by ̶0;Your World.̶1;
Move your world to the USB flash drive.
Connect the USB drive to a PC. Drag the map you wish to import from your downloads file to the desktop, for ease of use.
Download and install Horizon, the free ̶0;Minecraft̶1; map tool (link in Resources). Drag the downloaded file into Horizon.
Change the profile ID, device ID, and console ID values in Horizon to match the values of your USB save file.
Save, rehash, and resign. Do this several times via Horizon to make the changes stick.
Click ̶0;Save to Device.̶1; Save the new file to your USB drive.
Connect the USB drive to your Xbox 360 and open ̶0;Minecraft.̶1; It should recognize your downloaded file.