Here’s some answers for your questions. I’m afraid they won’t be very helpful:
1. The Google Maps API doesn’t support setting opacity for the map. You could try setting an opacity on the containing div, but I don’t think it would work.
2. Sorry, but no – there’s no copy function yet. You could copy the map at the database level by copying its row in table mappress_maps and mappress_posts.
3. No, Google doesn’t support tooltips for shapes, only for markers.