cory's_map_pack.zip

This download looks like an addon. You need to extract the downloaded zip and put the addon folder in your Garry's Mod addons folder. You should end up with a directory structure similar to below:

• steamapps
  • common
    • garrysmod
      • garrysmod
        • addons
          • Cory's Map Pack <-- Addon folder!
            • e.g.
            • lua
            • maps
            • materials
            • models
            • etc

• Cory's Map Pack/
  • ct_cityblock v20002.jpg
  • ct_dark passagev20001.jpg
  • ct_temple small0000.jpg
  • Information.txt
  • Maps/
    • City Block/
      • Ct_CityBlock V2.bsp
    • Dark Passage/
      • Ct_Dark PassageV2.bsp
    • Small Temple/
      • Ct_Temple Small.bsp

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