Thanks for your observations!
Honestly, I wasn't thinking about the positioning of the audio, I just created AudioPlayer2D nodes and they started in the top left corner of the screen. It didn't occur to me that that would affect the sound.
I just went back in to see what you mentioned about the two credits buttons. Turns out, when I duplicated the credits button to make the how-to-play button, I forgot to change some code that was from the credits button. So, the first time you exit the how-to-play page, it switches the name on the button to "credits".
Sorry about the logs mini game, I should have made it more clear how it works. So, there are three stages, and the timing gets faster each time. Every time you miss, you go back one stage. It doesn't make a lot of sense realistically but I wanted to make sure it was challenging.
Yes, the art is pre-rendered. I chose it for two main reasons. First, 2D is much simpler to work with, and second, I thought it would be an interesting style.
I hope this answered your questions. Thanks for taking the time to write down all of these notes, it helps a lot!