I finally sat down and finished this one, I've actually wanted to ever since I read the review in an old 1994 PC Gamer (this mag also had a review of System Shock, man I wish I'd kept it).
Anyway, what a great atmospheric and different adventure. The gore and themes would have been quite shocking back then, when everyone was kicking up a stink about such games as Mortal Kombat. The soundtrack is awesome. A few puzzles could have been easier to solve. I found the Diary of a Madman and manual on another site.