What I've figured out how to do for now is a thank you page (at least, it's supposed to work). I've put the initial text
here, so you can look at it. I'm sick right now (when one of your students is showing symptoms during the test, your own weekend could be special), so it might be off, but there it is. The payment page should go there after it is done, and it gives me something to customize in case anything changes.
I think a voluntary list of donors sounds reasonable, though I'm open to your thoughts on the matter. The "thanks" page could ask you to email if you'd like to be listed. A separate email is an extra hassle for the donor, but sending email is pretty easy, and you can confirm your payment was processed at the same time in that way. It also wouldn't take long for me to handle this each day (I wish it would! he he he).
There are a couple of reasons why I'm not for game fingerprints... it's an alpha so they'd likely have to be tracked and replaced after being destroyed, which could become a task. Also, depending on how it works, it possibly fixes the tone of the game (making it zany and anachronistic), and I'd like to keep that malleable. It also ties a payment to content distributed with the game, which is the kind of thing I'd really like to avoid since I don't understand the ramifications.