@monica See this post : http://forums.realmacsoftware.com/t/google-maps-changes-are-afoot/8105/14
Also to cut a long story short, Check for stack updates (update Map 2) then revisit the Map 2 demo page, and look at the FAQ section for how to get and assign your Google maps api key : https://www.doobox.co.uk/stacks_store/demos/map2.html