To all appearances, the dev does sometimes respond to requests, but not always. Some have apparently had better luck than others.
That said, you are advised when you purchase this product that you should back up your information (I'd have to double check, but I'm about 95% sure on this). As such, it's your responsibility, not the dev's responsibility. I think a better solution is needed, but does this mean you should be allowed to crack the game? Me, I'd say no. Especially since we don't actually have definitive proof that the original poster actually bought the game in the first place. Now, stop right there; I'm not accusing him of lying. I'm simply taking a big-picture perspective, considering all the facts. If the original poster deleted the email they got which registered Manamon, then there's probably no proof they can provide which demonstrates they bought the game. And even if there were, the fact that a crack is just floating around is not okay, because even if this user is legit and is only trying to re-access what he paid for once, that will not be true for everyone.
And there's still, of course, the issue of "having no choice". It's a game, people. There is always a choice.
Check out my Manamon text walkthrough at the following link:
https://www.dropbox.com/s/z8ls3rc3f4mkb … n.txt?dl=1