If you want to make a scenario for the faerun map, you can use my map/scenarion online editor at
http://dominions.realites.org/map_editor/
The editor is still in beta and some features are still missing (you cannot yet set starting provinces for exemple, but if you have some already set in your map file the editor won't mess with them), but you can use it to add magic sites and commanders, as well as terrain_types if you want to add more feeling to some provinces.
Whatever you do, when your scenario is done I will gladly add it to my editor and host it if you want.
If you have suggestion or bug reports to make about the editor, you can post them to the current beta thread :
http://www.shrapnelcommunity.com/thr...b=5&o=&fpart=1