The three parts in this image http://screencast.com/t/145CspmNBjq shows that two parts are below the plane... were moved not like the part on the left. I moved the two parts not knowing that they would end up below the plane. What caused this? I've tried to move but I couldn't move.
This image is to illistrate in the pathfinder that there are three solid bodies inactive one active, there are three other Solid Bodies not shown are active. How to active all Solid Bodies. http://screencast.com/t/6OInVT5LQFG