I've completed
The 7th Guest. The only puzzle I skipped was the microscope puzzle (which I've never been able to win in my life). The game works great. I've reported two bugs: a small (but very frustrating, as it tends to kick in at crucial times)
music bug, and a
minor bug that only occurs when loading a save directly from the ScummVM launcher.
I also found two major bugs: the acting is horrendous and the plot doesn't make much sense. However, I didn't bother reporting them, since they also occur with the original interpreter.
(And, in a way, they're part of the game's charm.)
Anyway, it's great that this game is supported, and I hope that Clandestiny will be as well at some point in the future (I've never cared much for The 11th Hour).
Game version: The 7th Guest, DOS, English
ScummVM version: 1.0.0pre042960, Intel Mac, Mac OS X 10.5