I'm still working on episode four, amazingly enough! (If it helps you to determine how deep in the episode I am, I just acquired the four instruments.)
The puzzles are getting more intricate and more intriguing; I'm loving it. The earlier episodes, it seemed like I could figure out all the puzzles in just a few days, but this fourth episode is quite challenging!
So far, this is my favorite episode to date. Great work all around!