Cute & simple game, I enjoyed it!
Also did not get the purpose of the C and D zip files. I initially thought it might be the Windows and Linux (or Mac or Android, etc.) builds, but it apparently seems to be the files for the web build (I guess so I can try the game on the browser locally), but when opening the index.html file it throws an alert mentioning the browser does not support multithreading and the game is stuck at the Unity loading screen.
I'm not really a programmer/developer (I'm primarily a musician/composer), so I assume some extra steps are needed to make those running (the contents from the C and D zip files).