I've recently noticed that my webstarts no longer function correctly on my Macbook Pro laptop since I started running Version 7.45 of Oracle Java. The "left slot" of the jrworkspace plugin system doesn't display (or it displays a fraction of a second and is then overwritten incorrectly by the jogl GLCanvas). The tool system also appears to be broken -- I can't rotate the scene. :(
To test your system for this problem, run
this webstart(from
this jReality tutorial).

If you do test your system for this problem, please post the results here so we can form a picture of what "subsystem" is at fault -- Java, Mac OS X 8, or something else.