I can confirm that's not the case. I still have the option of writing reviews for games I refunded and/or games which I played during free weekends and such but did not buy. That's solely based on time played and not ownership. Attaching my Nidhogg steam page to prove that, it still gives me an option of writing a review. Notice that I do not own it. (There's no "You own this game" label above review section)

Thank you for that confirmation, that certainly eliminates that possible reason. But I still think there are other possibilities at play and one shouldn't make strong accusations against a dev without strong evidence of foul play directly perpetrated by them.

Hello.

Because Undertale is not (yet) available on GOG, I'm thinking about purchasing the game from developer's website. However, I have two important questions. I already know the game is DRM-Free there.

1. The game includes an additional Steam key. I don't have plans to buy or redeem the game there. Is the key region-locked or does it have an expiration date?
2. If not, then I'm thinking about a deal - I will buy the game now and keep the key. When Undertale will be released on GOG and someone will be interested in a Steam version, he/she will buy the game for me and I will exchange the Steam key for a GOG key. Good idea?