How can we connect the fifth installment with the previous games in the series?

Archibald and Roland collaborated quite well. (Read the Might and Magic history by Demilich). We haven't finished with the third installment; there's just a temporary development standstill, but I hope we'll overcome it soon. Enroth is the world of the second and third games; it's also the mainland. The events take place in the world of Enroth, but on all three continents.