Hi Greg,
It looks like your Google Map Builder has some code that is causing background images (as well as itself) to disappear towards the end of your page. To fix this, maybe try adding the maps again to make sure no little details got left out? It also appears that some code in the maps is affecting drawing the map when scroll motion is enabled on the object. I'm still working on figuring out exactly what is going on, but if you have a chance please try replacing the Google Map Builder widget and see if this problem fixes itself.
Dana