Old topic is old.
But contact a modder/mapper to create a custom Tatooine map?
I´ve personally taken interest in GtkRadiant, so when i´m good enough i might be able to help you out =)
For our public server we only go with the default maps, never custom ones. You may remember though that we have edited the entities on those maps, even injected other whole maps into them. Entity editing is a completely different kettle of fish; one that we got sorted for the moment. Thanks for the offer though!