Great guide, thanks. Followed it very closely and all achievements unlocked when they should.
Don't know why so many people had trouble, can only assume they overlooked something, or maybe didn't finish the level properly. Anyway, hope y'all have it sorted out by now.
Yes there are a few typos and wrong collectible descriptions here and there, the formatting could have been better too, but the accuracy and shortness of the descriptions are commendable. Many thanks.