Tried running the program but could only get the white notes to show up. Was able to interact and play with them but the 4 GUI options in each corner in the screenshots wouldn't appear. Tried running the exe, zip file, and exe2 (also renaming the .pck file to GameJAM2.pck), so sadly couldn't make anything.
On the other hand tho, love the idea of make music with other people in this kind of format. A great concept for the limitation!