I have beaten Psychonauts and finished the story. 😀 I had almost given up.
I unlocked I Thought That Was Unbeatable, Piggy Figgy, and Victory Tour.
I still have Math is Hard, I LOVE PUNCHING!, Wolpaw Says Thanks, Holiday Dinner, and the secret achievement, to complete. For Wolpaw Says Thanks and Holiday Dinner, I will have to start a new game, though. I might not have to for Math is Hard, but it will mean doing a lot of the last few levels over again. 😡