You need to install the Guidance Automation Extension because it is a prerequisite to the plugin factory. I checked the link but it seems that it was moved to a different location that is why the installer redirected you to a different page. Anyway use this link to download GAX and install it on your computer.
http://www.microsoft.com/downloads/details.aspx?familyid=c0a394c0-5eeb-47c4-9f7b-71e51866a7ed&displaylang=en |