It sounds like proper GLSL 1.20 support is all that's missing, and it can't be that far off. The Penumbra games worked perfectly, after all.
Yeah, Penumbra: Requiem bored me to death after a while. The first two, however, reminded me of adventure games of old. Despite a 3d interface similar to modern shooters, it reminded me a lot of the original Alone in the Dark game. Since both are heavily inspired by Lovecraft, it's not a surprise.
Actually, I like horror games so much that I enjoyed the adventure/horror heavy Doom3, when many people hated it.
It sounds like Amnesia doesn't mess much with the gameplay, which is great, because it's just right the way it is. Penumbra: Overture was good, but with a few niggling problams, which got corrected in Black Plague.
If you're referring to my bug report, the GLSL errors are gone, I _think_ the remaining problems are FBO related, but I'm not sure? Anyway, it sounds like there's some interest in the game, so hopefully it can be fixed soon
Wasn't Requiem more of a puzzle-only expansion rather than a full game? I think it was released only as a favour to the fans?