Pop Up when user clicks the 'Register' button

It would be extremely awesome to be have the option in the Pop Up! plugin to be able to force a pop-up once a visitor clicks the 'Register' button.

One problem I'm having is my new users don't realize that they need to go to their email and validate their account after signing up. I downloaded the pop up plugin thinking I could force a pop up right after they click the register button that would have a nice graphic saying something like, "Thanks for registering... you're almost done! Go to your email account and click on the validation link to finalize your registration". This would be the perfect, in your face way of letting people know there is one final step to the registration process that they need to do in order to use the site.

Could this be added - an option in the pop up plugin to force a pop up when someone clicks on the 'complete registration' button.