In order to get familiar in a fast and pretty straight-forward manner with RadWindow for ASP.NET AJAX, I suggest you visit the online resources linked below:
Of course, you can browse the public forum as well in order to find a specific information/code sample concerning an aspect of the RadWindow object model/ features. There are numerous threads which can get you started/assist you through the development process.
If you think you have an interesting project implementation with the RadWindow that would benefit the community, we will gladly reward you for posting it in the Code library of RadWindow. So feel free to share your projects for others to learn more about all the amazing things RadWindow can do.
Finally, we will appreciate your feedback on the structure/content of the online resources - our goal is to continue enriching them, thus facilitating our customers even more.