I know nothing of Toolkit, but even I can tell you how to do that.
First, you have local areas, right? Ones with buildings and such, say inside a town. Then, you have your actual map - one which will display towns and such. So, once your guy reaches the edge of your town, say, by going west, the westmost edge will teleport him to a different board - the map. Once in your map, you'll have smaller icons resembling towns - so when a player walks into a town, it zones him into the town he walked into.
I'm sure others will be able to give a more thorough explanation - or did you mean something else?