I really want to like this one. I played it to the end, and you all clearly put in a lot of work and it shows. Sophia is adorable, the music and art are great (especially the backgrounds and the world map) and I love the theme. However, I got very frustrated by the wonky physics - especially when dealing with blocks and moving platforms. I kept falling through them, or boxes would fall through them. Sometimes, when I had blocks stacked on each other while on an up-down moving platform, the bottom block would just fall through. Sometimes, the platform I was standing on kept going up without me when I activated the music block. The jump also doesn't work consistently - like 25% of the time, I get a short jump.
I also think you could improve the level design. The music blocks were a neat idea and a few of the levels that use them really shine. However, it felt like too many levels boiled down to "stack 2 blocks to reach the note" or just "grab the easily accessible keys and go through the doors in order". Also, some of the later levels felt very simple, like they should have been in the first or second area.
There's a lot of potential here, and I hope you polish it up!