I get that, but according to this:
https://falloutmods.fandom.com/wiki/Exit_grids
"If you want it to send the player to the world map, leave it alone as the default setting will do just that.. ( if you press f8 to test the map, and press f8 again to stop the test mode, you will notice the editor has turned your green exit grid to brown. )"
As I understand it, by default the exit grid destination variable is set to "-1" as mentioned here:
https://falloutmods.fandom.com/wiki/Fallout_2_editor_introduction
"Set Exit Grid Data - Sets the Exit grid data. After setting the data, you will mark the Exit Grid objects with the other two options. Entering -1 in “Exit Grid Dest Map” option will send the player to the World Map."
I have been able to set exit grids to refer to a map, but when I set it to default, which is supposed to be world map, and walk on it, it crashes. So my problem seems to be one of having the world map not working in the mapper?