Which one are you trying to use, what have you done to prepare it, and where have you put it?
I searched for the mod and found there are two versions and a variety pack:
(Version 6 - FULL) - Requires Babylon, Spain/Inca, and Mongol DLC
(Version 6 - Non-DLC) - See "Non-DLC" section. This version has not been released yet.
(Variety Pack 1) - Includes five new random maps and two new civilizations. Compatable with both versions, NOT with vanilla civilization V.
I already have the MODS menu enabled in my copy of Civ5. Here are the steps I followed:
- downloaded the Non-DLC version
- removed the apostrophe from the .civ5mod file name, as Ez7z seems to object to it
- expanded it into a new folder called "Putmalks Ancient World" using Ez7z
- the new folder contains /Art, /LUA, /XML folders, and a file called "Putmalk's Ancient World (No DLC) (v 6).modinfo"
- moved that new folder into ~/Library/Application Support/Civilization V Campaign Edition/MODS/**
- launched Civ5, selected MODS -> Browse Mods, and enabled Putmaiks Ancient World.
- clicked Back, selected "Single Player" -> Setup Game
- I could then select one of the new Civs and start a game.
** I'm using the App Store version of Civ5. If you have the Steam version you need to put it into the appropriate MODS folder, typically:
~/Documents/Aspyr/Sid Meier's Civilization 5/MODS.