The documentation regarding Google map keys unfortunately only mentions vehicletracker. VehicleTracker and BuddyTracker each need a separate key from Google.
I recently answered a similar question here: http://franson.com/forum/topic.asp?TOPIC_ID=5779
"First, note that each Google key is only valid for a specific url. Thus you need to obtain a separate key for each application you intend to use (i.e. one for BuddyTracker and one for VehicleTracker)
The files where the keys are to be inserted are:
At the top of each file above you should see a couple of lines looking something like this:
<!-- REPLACE THE GOOGLE MAP KEY BELOW WITH YOUR KEY AND REMOVE THE COMMENTS -->
<!-- END GOOGLE MAP KEY SECTION-->
Simply paste the key you received from Google between the separator comments.
!Note: The Google keys are _case-sensitive_, that means you need to paste the key/url _exactly_ as you got it from Google.
We intend to simplify the handling of Google keys in future releases, so that you shouldn't need to do this manually."