Spunky, make sure your using a Pro version of LimeWire! Make a backup copy of the LimewirePro theme and move or delete it from the directory. Then extract the LimewireAero theme into the folder.

If you've done this restart LimeWire or refresh the skins folder in the program and select the theme. If the skin doesn't change then select it once more! Remember it will only work with a Pro version!