That's more of a question for a copyright lawyer and economic analyst than a computer programmer, but I think that a) yes, if you wanted to retain the copyright you would have to copyright it (and software is considered a copyright, not a patent. Just to clarify.), and b) it probably wouldn't sell in the mainstream market, so I would recommend some other means of distribution. You might want to consider making it free, but if you're bent on getting a profit or at least breaking even, you might stand a better chance of marketing it as educational software rather than a computer game (I'm assuming some or all of this game is geared towared teaching social skills to autistics). Also, you might want to see if you can get either an autism non-profit or a government mental health agency and see if they will endorse your product so as to make it more appealing to mothers and the like.
As far as beta testing, you might be better off having experts test the software first, then maybe have some med to high-functioning autistics test it and see if they like it.
Of course this is all speculative BS on my part, since I'm not familiar with the process. But maybe talking to an expert in marketing or copyright law will help you get started.
Cheers,
Roxas
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