I agree it is not clear to figure what can be accomplished with a realistic physics plug in.
The feature list does not really say you can do this or that; it is more like a carpenter tool box. It is how you combine the basic feature that creates amazing things.
It is better to start easy and gradually add more complexity as you go along. Here is for example a video if found over the Newton forum of something that is possible but the engine would not let you think it could be.
http://walaber.com/misc/tramp15.avi
I think if some of the more advanced users can write basics tutorials, it will be great for us the less fortunate .