Thread:GandalftheTurquoise/@comment-28554571-20160710234221/@comment-25101690-20160711143532

You want to switch the map? I have a little experience with that already.

If you switch the file using a resource pack, then the displayed map will change but the world generation will be the same. It's recommended to use a map with the same size as the original map for this because otherwise a lot of bugs and random crashes can occur on the map display menu.

If you switch the map file inside the mod file, the mod will use this map for the world generation. Here you should also use a map of the same size. I couldn't find any hint for the size in the code but I ran into problems when I used a different size. You also have to make sure that the map only uses the colours also used on the original map. Any colour that is not recognised will generate ocean biomes.