I’m always seeing “first CD-ROM game” citations that are totally inconsistent, or which cite games like Myst, so I decided to put together a timeline of all the candidates - and ended up calling into question the point of “firsts” lists in the first place.
Fun article on retro CD-ROM games put together by @misty
I think the 7th guest has a puzzle now that is almost impossible to beat due to the way it calculates the answer and todays processor speeds. (The microscope puzzle). You can read more here (Obs. Spoiler):
https://www.dosgameclub.com/forums/topic/the-dreaded-microscope-puzzle/
Can recommend clandestiny if you like the kind of puzzles in 7th guest. It’s a fantastic game.