Very good! And a bit scary...
One annoying technical issue - some of the text messages don't get replaced when they should, e.g. messages saying "it's too dark to go there" after I've turned on the light.
The diary text was quite long, I didn't mind b/c it was fascinating, but it is more enjoyable usually to reveal the mystery/history in pieces... (though surely more difficult to write, so I can't remove another half star for that).