What are some good resources for learning how to AppleScript with Xcode 4.3.2?
Mac OS X Automation has sample Xcode projects and a few videos for getting started with AppleScript in Xcode. They also have a comprehensive book, AppleScriptObjC Explored, which you can buy from their site. (I can't vouch for it as I haven't read it, but their free resources are excellent.)

You can start here:

http://macosxautomation.com/applescript/develop/index.html