(a) The Mac App Store does not offer a way for existing users to upgrade.
(b) The process of upgrading the actions for Lion and the Mac App Store took a considerable amount of development time, that is, time away from my wife and kids). So, I'm afraid that I must recoup some of that investment so I can continue to devote time to upgrading and releasing other action packs.
So, if you'd like to upgrade, then I'm afraid you'll need to purchase the updated action pack from the Mac App Store.
Thank you for your understanding.