The codes were available before the game was released.
Removing the walk thru walls code removes the walk thru walls capability if the game is reloaded.
You cannot go everywhere with walk thru walls. Sometimes you cannot leave *spoiler warning *
You cannot enter the palace in Kaocho or Belinsk by the door. You can enter these palaces from the dungeons and exit that way. Belinsk however has no exit that I can find. I could get in but I could not return.
You can walk thru walls over the rubble that Blados dynamited over Konpa Cave.
--- GoldenSun/Crossbone Isle diagrams/ 18 teams known http://s174.photobucket.com/albums/w89/SwordOfWheat/Weyard/PicsNao/