A question. I gifted a GOG game over a year ago - it says the code was 'sent' to the person in question but they never actually redeemed it. If I give it to somebody else manually (since I don't think I can re-send), will it simply state the game is no longer available to the original person if they tried? Said person is never actually going to redeem it, not after all this time, but I didn't want a messy technical situation re: ownership.
If you have the (unredeemed) code (is the same as the one found in the gift link, also found in your e-mail and in your account section "Gifts"), you can send it to a new person and that person have to activate the game here: https://www.gog.com/redeem
The original person wouldn't be able to activate the game anymore and will receive a message of "code already used", or something like that when and if he or she tries it.
Also, in the section of Gifts you can confirm if that code was used or not.