Activating Add-on, getting: ImportError: No module named 'bpy.utils.previews', 'bpy.utils' is not a package Add-on  Pro Lighting Skies Demo



This message error pops up when I follow the steps on how to download.  Somebody please help me.  I followed Andrew Price's directions on his website, Blender Guru, but it will not work.
You need to update to Blender 2.75. Versions prior to this don't have bpy.utils.previews which is used for custom ui icons and preview images. You will also need to install the add-on again, probably.