Looks quite cute, clean and made with love! Nice work with art and sound.
Lacks intuitivity. While player is presented with controls, it's very unclear what do they do. Even with description on the submission page (and players won't be reading that). As a player I see stimulus (as a new object on the floor or a blinking sign) and I want to interact with it the easiest way possible... Pressing 'z' gave me sounds but I couldn't get any further in understanding mechanics.
Postjam version is much better, thanks. But I would advise you to add gradually filling progress bar when dealing with objects on the floor/cracks because it's definitely not clear that you need to hold 'z' instead of pressing it once. Even shortness of a sound indicates solitary action.
Overall, nice and cute. Thank you!