I wrote:

>>> Dear OS Xperts,
>>> Just installed OS X and having problems opening FB Editor files in Classic.
>>> 
>>> Double-clicking a file launches the Editor but the file doesn't open and
>>> instead I'm presented with an open dialog. The file opens when selected in
>>> the dialog.
>>> 
>>> Rebuilding the desktop doesn't cure the problem.
>>> 
>>> Everything works fine after re-starting under OS 9.
>>> 

I should have added that plug-ins and Editor Help menu items don't launch.

Bernie