>   So, how does one stop execution?  FWIW, I'm on a mac.  Thanks!

Not really sure what you mean by "stop execution" (of what?) but you might
try the Cmd-. (period) combination to interrupt Squeak at what it's doing
at the moment.

Hope this helps,
  Andreas
-- 
Linear algebra is your friend - Trigonometry is your enemy.
+===== Andreas Raab ============= (raab at isg.cs.uni-magdeburg.de) =====+
I Department of Simulation and Graphics      Phone: +49 391 671 8065  I
I University of Magdeburg, Germany           Fax:   +49 391 671 1164  I
+=============< http://isgwww.cs.uni-magdeburg.de/~raab >=============+