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I was checking out the special features for this, and I noticed that the manual is a new one made for the 15th anniversary edition. It's a great manual, and has succinct information on the game, but it made me remember the DOS version I had, which came with a very different "manual". It was done as a strange set of documents that didn't really explicitly tell you about the game. For instance, the section on how to use the gun was written in the form of a journal entry by the protagonist of the game, where he writes about how he has figured out the workings of the weapon. There were some other parts too that I don't remember, but were similar in style, serving to add to the atmosphere of the game rather than be a strictly functional manual.
I have no idea if Eric Chahi had anything to do with these materials, or if they were added by Interplay. I was unable to find them on replacementdocs. Anyone know anything about these? Are they different from what came with the original Amiga version? Any chance GOG could find them and add them as extras?
I found it in French on an abandonware site:
Maybe it can also be found in English on some other abandonware site and could be added to the bonuses by GoG...