How do I load/use a custom map?

[Edi]

You need to do as follows: Load the map file in the editor, then assign borders as you see fit and check the nostart checkbox on those provinces you want to disqualify as start locations. Save map file under different name. Then open new map file and the original in text editor, and copy everything except Province Names/Terrain section from old file to the new, then save new file.

You're done. The map editor is the only practical way of reassigning neighbors and terrain without it being a huge hassle.

Edi