It's Elementary -- Rev Keeps Crashing!

[Judy Perry]

Okay, I'm trying to maintain a sense of humor.  Rev has crashed on me SIX
TIMES during the last 90 minutes.

What am I trying to do?  One card in one stack.  Three fields:  N1, N2,
Answer.  Four buttons:  Addition!, Subtraction!, Multiplication!, Check
Answer.  The first three buttons generate random(9) for the first two
fields and puts the answer, whatever it is, in a global variable
theAnswer.  The "Check Answer" button then checks to see whether the user
has entered the appropriate number in the third field.

Everything seems to work for a while and then just inexplicably crashes.
No moved picture/movie/sound files, just pfffffffft!  buh-bye.

Any ideas why?  Mac OS 10.2 (Jaguar) on a TiBook which should have plenty
enough RAM for elementary math.

Judy