I see this has been requested several times over the years. I think there is renewed interest in this calculation after the recent article in Oct 2017 issue of BYO with the equations and discussion on calculating the diastatic power of your recipe. The article is "Brewing by Ratio" by Aaron Hyde on page 45. Since the DP is already included in the properties of the malt it should be a simple equation with a DP result field that could be added to the design page.

Thanks Brad for an awesome and indispensable application!