What you are doing is fantastic, keep up the great work. At some point in the future, it might be good to include on the edges of the map, a clearly defined edge, so that when you put the mouse over it, the map scrolls in that direction. I see it as something like a tab with a picture of an arrow in the centre.
Another good feature might be to add a hand tool, so you can click and drag on the map to see nearby areas. Again, thanks for your efforts, can't wait till it's up and running!