The WCK framework is something I used recently on the Blackberry Playbook version my Susie Starfish app. Moving into the world of physics is a big step for any flash dev and I feel the WCK framework is a good way to get up to speed on some of the basics.
Moving onwards I wanted to be able to appreciate how the framework works a little more so I could begin to program aspects myself through pure code in a way that was more familiar to me than the Box2DAS port. My reasoning is that I just wanted to be a little more in control for when I come to memory management and the general interactivity of the project. The following code snippet is a quick example of a box falling onto the ground and firing off the events related to such an activity.