You're issue sounds really strange. I wouldn't necessarily blame Gateway yet (Or imply that they're being malicious) simply because it's a beta release. Might just be something screwed up for some reason in Gateway's implementation, or it could really just be a fault of your 3DS (Unrelated to the current release).
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I'm not so sure it's just me, since Kazuma77 had a similar problem, though I don't know if Kazuma has a hardmod or not, and he was on O3DS. In any case, I'm doing more testing with my Anker USB adapter, and I think I can rule that out as the culprit now. It's going to come down to my hardmod or the SD adapter it uses, but that still wouldn't explain why the Gateway menu consistently fails to restore a dump.