[AccessD] Framework Discussion - set up question

I;ve been not able to read all the mail on the FW closely for the past
week, so sorry if this is a repeat.
I "get" the idea, and the form scanning, but I don't see exaclty where
to tell the fw that , for example, on 2 different combo's Not In List, I
want combo1 to pop a form for data-entry, but combo2 to silently undo
and reject the newdata.  Should this be set in the Tag property?

Tia,
Steve