The Medieval Pack 3.0 contains a number of individual mods, which are fully integrated to provide a one-step installation process. To use the Modpack, you will need to have already installed the 1.2 patch and 1.21 hack, which are available at Apolyton. Then you need to do is use Winzip to unzip the components of the Pack into the Call-to-Power folder. If this is your first time using a mod, you will need to adjust a setting in the userprofile text, which is detailed in the Miscellaneous readme. That's all you need to do to get the mod to work, though I strongly urge you to follow the instructions listed in the 1st Readme.
Notes: 1)For multi-player use of the modpack, it is necessary for all of the participants to use the same version.
2)If you want to switch back and forth from the modpack and the original game setup, such as when you go from single-player to multi-player, you will need to switch out the aidata folder. Copies of both the original and the Medieval Pack versions are contained in the Med 3 Readme folder, where this file is placed. The folder the game uses is found in the ctp_data/default folder.