Thanks so much - all working great now.
Just one final thing: you have to click the little flag icon that marks the address on the map in order to see the address "callout". Is there a way to have that address appear by default on the map that initially appears - just so they know that they're looking at a map of one of the locations? They may not know that they have to click it either which is why it would be good for it to be shown.