There appears to be a bug... somehow I got to level 18 and now whenever I click on any clickable boxes it makes the noise but they don't disappear. I'm running mac os x 10.6 and chrome 5.0.342.9 beta, if it makes a difference. Overall quite fun though. 3/5, 5/5 once the bug is fixed.
Oh, and if you're in the finale mission, trying to figure out who wants to kill you (future tense), clues telling out what the murderer WAS and WAS NOT (past tense) is a little strange.
I'm really enjoying myself, but you've GOT to clean up the boundaries of the subjects -- it's VERY easy to mis-click, and this can get really frustrating when you're trying to get one of the long badges or are up against the time limit.
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