It looks like you were told that a check box on a stamp cannot be clickable after it is applied, which is true, so what you say you want is not possible.
As mentioned in the other thread, what you can do is prompt the user at the time the stamp is applied and ask whether the resulting check box should be checked or not. This type of stamp is known as a dynamic stamp and there are specialized scripting techniques that need to be used. Have you had a chance to go through any of the tutorials you were directed to?
I have to go see it yet.