With Auto-Download enabled, and with a valid connection to the internet, zoom out all the way by pressing and holding the Zoom Out rocker button for 10 seconds, then let go of the Zoom Out button. You should see a map of the whole world. If you do, then use the Zoom In button to zoom in, and tap the screen to center on that point on the map, to get down to New York City.

If you don't see anything, then your URL Format may be invalid. What is your exact URL Format string? Try this URL and see if it works (the "v=" part may be different from yours):

http://mt.google.com/mt?n=404&v=w2.99&x=%d&y=%d&zoom=%d