all things you want to change @go 0 is this....
svnsrcmapatcommand.c
{ MAP_PRONTERA, 156, 191 }, // 0=Prontera
this
clif_displaymessage(fd, " 0=Prontera 1=Morroc 2=Geffen");
then
if (strncmp(map_name, "prontera", 3) == 0) {
then instead of changing
#define MAP_PRONTERA "prontera"
define a new map
#define MAP_CUSTOM "Custom"