The writers on the Blue Ray DVD actually said that people could leave SB before the curse was broken, but that bad things would happen. Gold didn't have his FTL memories at the time Henry was brought to SB, so he wouldn't have any memories to lose. They used the conversation about Red going to Boston, but then Grams had a heart attack, which was because of the curse and it kept Red in SB. But I think that Pinocchio or someone like him brought Henry to SB. Didn't Regina say that she changed his diapers since he was 2 or 3 weeks old?

I'm pretty sure it was Regina in this episode, because of what they said on the Official Podcast about the episode. She is just really similar to her mom when she is being evil. I think they have a lot of the same traits.