This article is called extended guide is because there is already a security guide in the Yii tutorial security section. but that guide is not complete in the sense that it does not rise the developers' attention to some other commonly happening attacks: SQL injection and magic URL, which can be major vulnerabilities in your application without much caring.
Installing WAMP on XP was pretty easy; W7 is not so trivial. It's not difficult once you know, but it took me best part of a day to figure out and required gleaning various bits of information from around the web; this tutorial brings it all together in one place to (hopefully) make other peoples lives that bit easier. It does assume that you are reasonably happy configuring Apache, PHP, and MySQL and mainly deals with the W7 quirks.