TheEnigmaticT: I'll just toss this out here: GOG.com isn't the developer of the game, so any reply from us won't count as an "official" reply from the devs.
I know that they're hard at work at CDP RED to address the issues that some of you are having with this game, and hopefully we'll hear more news from them soon.
That said, any requests that you'd like to make to the CDP RED devs would more profitably be addressed to the fine folks over at thewitcher.com, since I couldn't say if CDP RED reads our forums or not.
I'd like to do that honestly, but the witcher forums are still down. I've emailed but thats the best I can get right now.
Gigantoad: Jesus people... I have EyeFinity with triple monitors too, but you have to realise this is an absolute niche. Very few people have this, you can't expect game studios to cater to these select few as if their life depended on it.
Falcon2045: The point is: If it was implemented correctly in the first place, we would not be here. It would work just fine.
The Problem is, that the game is hard coded for 16:9 resolutions. That's why Eyefinity users get black borders on left and right and that's why 16:10, 5:4 or 4:3 users have black borders on the bottom or on the top.
A correct fix/implementation would be a benefit for all users that do not have a 16:9 monitor. And I guess, this is the majority of all players! Exactly correct.