Hi dude.
Just do this:
1. Go to your WoW dir.
2. Find and enter the "Interface" folder.
3. Then you have to do one of these things:
a) IF the folder "AddOns"
exists then you can just unzip your .zip file into the "AddOns" WITH AN OTHER folder called the same name as the UI Mod fx "CT_Mod".
b) Now if the folder "AddOns"
DOESN'T exists in the "Interface" folder, then the "tricky" part comes:
You simply just add a new folder called: "AddOns"
Then it would be like this:
/Interface/AddOns/*****/unzipped-files-here
(***** = a folder with the name of the UI Mod)
Well explained?