Firstly I'd just like to say thanks for your reply :). I want to be able to interact with the "ball" in a way which allows me to drag it around the screen (whilst clicking and holding on it with the lmb) and then once released will fall and stop on the immovable object (the floor).
The problem I have is, during the process of dragging, positioning the ball you can drag it through the immovable object. This is the interaction that I want remove.The result i'm looking for is that when dragging, when the "ball" hits the floor, it will only roll a long it etc (move left to right visa versa) but not below the floor.
It's basically the achieve the placement of physical objects :).
Is this of any more help?
EDIT 1: One partial solution seems to apply physics force to the mouse x and y position. It means you can drag the object through the immovable one. However, it's not exactly smooth and the object rotates circularly around the pointer on the screen.
EDIT 2: Did some more searching on the forum, found your thread on mechanics and such. Have a partial solution (from a capx your linked + I added in few physics events). Only issue is, I can't seem to get more than one object working at the same time without it going crazy. Here's a link -