I'm not 100% sure here, but when I had a similar problem I resolved it
by using the OnValidateField event for the relevant dataset.

My problem was related to a VARCHAR field (TIB_Edit component) not a
check box, but may help.

Rgds,
-Ryan

> If not, how should I immediately respond to changes in data when it is
> edited (and without being forced to leave the field to know that change
> has occured). Is it too much that I want to achieve ?
>
> Thanks in advance for any input.
>
> Regards,
> Tom