IT WORKED!!!! Thanks for the help!

Thanks Anton. Could I install SU7 and use it when I'm going to need physics? Is it still available?

I am running Sketchup Make on a MacBook running OS 10.8.4
I have been using Sketchup for some time now and just found out about Sketchy Physics.
Finally got SketchyPhysics installed and watched a couple of tutorials. Everything works as expected until I press the play button. Sketchup locks up for a few seconds and then crashes.

Anyone have any advise? PLEASE!!!!