Choose the map (and respectively game pace) from the drop down menue. Once you're in the game go to Main Menu - Mods - Activate mod - Next - Single Player - set up game not Main Menu - Single Player - set up game. This gives you a new challenge once the optics have been researched and you have caravels. This map pack contains the new Atlantic Discovery maps which are basically the same Europe scenarios combined with a North American continent to explore and colonize.
It comes in 4 different flavours: There is a separate one for each game pace option, allowing you to choose whatever game speed you like, as it cannot be changed in one scenario. The map has slightly been reduced in size, from big to standard by cutting off redundant sea tiles at the top and left side of the continent. I tried to give the terrain an even more realistic look and covered the map with resources, trying to make it well playable at the same time. There are true start locations for all European Civs to date. I initially modified Dale's big Europe map for private use only, but decided to share it with you (for those who rather want to download maps than create them themselves).