I can tell you:
- you must configure your map in few files (worldmap,fos or config.fos) I can't you tell it more because I don't have sdk, so I can't check this, something like this
- you must have mask file of your map because you can color water space, etc
- I am not sure but you need cut your map into pieces
I recommend you read wiki about new map, fallout 2 worldmap make
Good luck.