http://www.giveawayoftheday.com/clipdiary-21/
I dl'ed Clipdiary V2.1 on two laptops from here on April 26th...which was 13 days ago. I suspect your activation of the software did not register the product.
I just updated iTunes to V8.1.1 on this laptop and as expected, it had no impact on my Clipdiary registration.