Put all the files in that zip/rar to >>>>> CustomMaps If you do not have a CustomMaps folder.........Create it! Below is where to put the files depending on your Windows Version.
For Vista >> C:\Users\User_Few\Documents\My Games\Unreal Tournament 3\UTGame\Published\CookedPC\CustomMaps
For XP >> C:\Documents and Settings\User_Few\My Documents\My Games\Unreal Tournament 3\UTGame\Published\CookedPC\CustomMaps