offline or online?
FOR OFFLINE USE ONLY:
Open up notepad and paste in the following:
HTML Code:
GRMAP001
WIDTH 2
HEIGHT 2
LEVELNAMES
"level_name_01.nw","level_name_02.nw"
"level_name_03.nw","level_name_04.nw"
LEVELNAMESEND
In my example I specified that the GMAP was 2 levels wide and 2 level high. You would change the values for width and height to fit the dimensions of your overworld. You would also add the level names you're using inbetween "LEVELNAMES" and "LEVELNAMESEND" formatted with the top levels of your overworld to the top of the list.
Click "Save As", name it something appropriate, and give it the extension ".GMAP".
Open up the Graal editor and in one of the levels you're using add these lines:
HTML Code:
if (created) loadmap YOUR_MAP_NAME;
It is important not to put ".GMAP" here because it assumes what the filetype is.