[lowfighter]

Zo, just changing map_c allows only small changes like deleting rivers adding small lakes and adding small patches of ground. So a small island can be enlarged maybe make it twice as big. The problem is that map_c as scrambled as it looks doesn't cover all the map but only the portions which have both water and land. So it covers the coastline and river/lake places only. MapCtgatable tells the program where to place those portions on the big map. If you could decript mapctgatable, you'd have the key to create really new maps with land and water where you want...
So with small islands it's possible to enlarge, by painting with white mapctga at the right place. Here's a shot of the british island maybe enlarged by 70% or so.