Nice twist with a good story. However I found most of the things you have to do aren't intuitive, and I just figured them out through trial and error, or by looking them up here. Personally I like it better when the game gives you hints (even if they're subtle) about what to do with items when you look at/examine them. (Like the picture frame in this game did, but then the plug hole in the sink didn't.)
Just finished, happy ending with four trophies... a little disappointed because I had the fifth trophy (Explorer) but accidentally shut down the game without saving. When I reloaded from an earlier save, I couldn't get it again, even though I had the koob dlo when I left the evarg.
In any case, CJ592, this is the best in the series so far and I enjoyed it immensely! Some of the puzzles I had to come here and get help on, but when I found the answer I pretty much always thought, "Of course! There was a hint about that!"
I think the introduction could offer some more direction with what commands are available (instead of having to find them here in the comments, where there are a lot of spoilers), and in general I would change how the communication works - see my previous comment about getting suspects to comment on objects. I would like to see much more commentary from the characters about items, even if it isn't something they're interested in. If the question is completely irrelevant, then a generic response makes sense. At least that way the player knows they're asking something that should be asked of other characters. I guess that might be a lot of work though! Oh, and grammar-nazi tip... It's "could have" or "could've" not "could of".
I'm looking forward to trying some more Craig Dutton adventures!