You need DPaint. Load the file 'CIVMAP.lbm into Dpaint and save it elsewhere. You can now draw your own world using the following color sequence:

Light Green = Grassland
Dark Green = Forest
Light Blue = Jungle
Medium Blue = River
Dark Blue = Oceans
Brown = Plains
Purple = Mountains
White = Artic
Yellow = Desert
Red = Hills
Grey = Tundra