I'm working on a project involving Sparrow+Box2D (my first Sparrow project). I came across this demo:
http://www.codeandweb.com/blog/2012/05/07/physicseditor-sparrow-box2d
However it was surprisingly out of date for something less than two years old - it uses Sparrow 1.4 and OpenGL ES 1.1. As a personal challenge I decided to try to update it. After working on it for a week, I successfully got the sprite to display and fall...to the ceiling. I'm not sure about posting my example as a reference, but it would be extremely helpful if someone could tackle an updated version of this.