The game looks great and works mostly ok, although the game lost my autosave after the first chapter and I had to ask for a savegame from Killmonday. The problem for me, a long time adventure fan, was the low difficulty of the puzzles. It almost felt like it was aimed for children judging by how easy the problems were. But of course, it can't be for kids because the game is pretty brutal and scary. Also, as a screenwriter I did think the script was not very strong, and there were very long parts where the player couldn't do anything else but follow the characters' conversations. All in all, a pretty big disappointment for me.
The story is great, as well as the characters (apart from the main bad guy). Episode 4 kept freezing on my Win7, but apart from that the gameplay was ok (not great, but ok). The whole game was refreshingly long, according to my steam, I spent 8h playing it. And I didn't even get stuck very often.