Dragon Quest VI: Realms of Reverie Q&A

Is the walkthrough for realms of revalation the same walkthrough as the realms of reverie on the ds as i cant find a walkthrough for the later game , please help me as im realy stuck on this game, started it twice already
from dawn

I have found out about alltrades abbey from dwarf. Talked to king. Found ruins in phantom realm. What next?

At what part in the game am i able to input the codes posted in the cheats section. Do i enter one code as the characters name and then that will allow me to enter the others? Or do i start game play as "any name" and later would i be able to enter cheat codes?