Go to Windows -> Rendering Editors and open up the the hypershade window. In Hypershade, click file -> import and browse to your downloaded file and voila, that's it. If you save the file into the appropriate AW location (i.e., C:/AW/ShaderLibrary/Shaders/), it will also show up in the shader library menu in the hypershade.
"Terminat Bora Diem, Terminal Auctor opus."