A couple of things about Gray Matter that I hope people will find helpful:
When I finished chapter two, I found that everything was "100%" but the chapter would not end. It turns out that I had exited the Carfax phone booth by using the map shortcut (upper left corner) instead of backing out by using the exit icon (lower left corner)
Apparently this bypasses the trigger to open the next chapter; a little slip-up on the programmers' side. I have seen other players complain about being stuck, and perhaps this is why.
Another odd thing: The automatic cutscenes play correctly, but when they end, they always play again, this time without the voiceover. (I was on the original beta-testing team for this game, and I don't recall that happening to anybody.)
That will be ten Dramoi.