Installing maintenance releases

I installed WF2 F000 from CD. Now I've downloaded WF2 M020 from the web, it's a 300 MB zip file. I extracted all the files to a temp directory. There is no setup.exe or ptcsetup.bat files. What do I run to install this?

Nevermind! I just saw that I have to download 3 zip files. I'm sure the installer is in one of the other files.

Someone just told me that the zipped files need to be extracted into 3 separate folders. When you're ready to install, just double click on Folder 1 like you're popping in the CD.