As Frank states, we don't want to support piracy here on Arqade. Yes, people will always pirate stuff, and yes, those pirates can see the error in their ways and buy a game they've previously pirated, but that doesn't negate the fact that they originally pirated the game.
This runs deeper than just pirates having a change of heart though. There's also issues surrounding legality that I wont pretend to know everything about, but suffice it to say if the Arqade or the Stack Exchange network were to openly support cracks, key-gens, DRM workarounds, pirated games or anything else of questionable legality, then that opens up a doorway for litigation to be brought against the company as a whole, and possibly individual users of the site.
Quoting agent86 on our stance toward not-quite-legal games (emphasis mine):
When it comes to legality, we tend to err on the side of assuming good faith here, and only prohibit questions that are clearly on the wrong side of the law, the terms of service, or the EULA for the software in question. <snip>
This means that outright discussions of piracy, EULA/TOS violations (game hacks, etc) are off topic, but most of the rest of the legal questions surrounding gaming we leave alone. For instance, emulation and issues with emulators are considered fine and on-topic.
What I take away from this, is that by aiding a pirate (even if they bought the game eventually) is off-topic, as it is an outright discussion in support of piracy.
If anything, it discourages people from buying legal versions in favor of keeping their progress.
I disagree. By answering your question and having it available for future readers, we are then providing a resource that pirates can use to justify pirating the game, with a thought process similar to "Oh well, I can always buy it if its any good, as my progress will carry over to the bought game".
You're right that we should be encouraging people to buy the game, but realistically the game should sell itself through descriptions of gameplay, mechanics, or storyline, not the ease at which one can pirate it and then buy it, as is your case.