Master page map annoyance

I added one of these guys to my template so that specific master pages are linked to element types. But whenever I open a file, I get a message telling me that all master pages will be reapplied, do I wish to proceed? It's very annoying when I open a ditamap that contains many topics because Frame makes me confirm the reapplication of master pages for *every* page generated by the map. To top it off, the reapplication doesn't even apply the master pages that I have assigned in the master page map. To do that, I have to select Format > Page Layout > Apply Master Pages. And that uses the map and applies the proper master pages...woohoo. But why do I have to go through all that bother when I first open a file? And how do I make it stop?