it's simple i found a bug that when you fight V after Atlantic City he gift you an ultra ball, but if you lose and go again, he do it again, i did it 3 times to test it, and yeah, you can do it always :B
Just saying. . .
great hack, im argentine and it's a great job.
An another one, when you finish touching the triangle of arceus and get the pokemon, you go out of the "house", if you enter again, you will get the pokemon again :D