To run the Ability macros, you'll need to have the Microsoft script engine installed. This will already be installed if you have Windows 98 (or later) or if you've installed Microsoft Internet Explorer 4.0 (or later).
If you haven't got the script engine, or are not sure if you have it, or you want to get the latest version, you can download it from the Microsoft web site:
http://www.microsoft.com/msdownload/vbscript/scripting.asp
Note the link is above is liable to change – if it is out of date as you read this, try searching on the Microsoft web site for "vbscript" or try the scripting home page: