Changing map size

I used to have a program that would let me to reduce or enlarge map sizes by swaping the terrain with a different one. Anyone know what program does that?

... you can change map size in World Editor, you can swap terrain too. Maybe that program you were talking about was World Editor?? :)

Can u tell me how to change map size?

Map Properties

That just adjusts the playable area, I wanna reduce the map size.

check off the "modify map bounds" box..... :-/ look more carefully next time, please.

how does one swap the terrain?

advanced>modify tileset

and tere are ways to do other things with terrain (i dont have the WE open ATM) look in the menus for more info :)

Unfortunately swapping tiles is very limited in the standard World Editor.
I can recommend WEU for that task. (it has an external app that can modify the tileset)