It was in fact included that you can center using both buttons at once, I tested in opera GX and it worked. And thanks for the review!
Oh nevermind, I didn't realize it was mentioned in level 3, and I guess that I just didn't need to use it until level 9, so sorry about that. I did notice a bug as well after the fact where the music starts playing a separate instance on top of the previous each time you go to and from the options, but that's not a big deal since you don't have to use the options. Possibly something to patch out later though.