How to apply the skin:

1.  Navigate to the directory to where all your WindowBlinds skins are kept. (Usually called "WindowBlinds" under the "Public" (Vista) or "Shared Documents" (XP) directory.)
2. Extract the ZIP file in the "WindowBlinds" directory.
3. Overwrite the "UI" folder.  All the originals are still there. (They are named ">filename<_2.png".)

Enjoy!