The rotation of the block placement potentially causing blocks to no longer be supported and fall was a really interesting mechanic. It forced you to be a little more methodical about things.
A tiny criticism, but for short jams like this. If you realize that you aren't going to finish everything you planned, put something as simple as "You win" text at the end of the content you have so far. You don't need to kick the player out of the gameplay loop or anything like that. But just letting the player know they did everything there is to it goes a long ways.
My brain hurts trying to explain to myself why that pink rolling duck combined with that music is so likable. It defies all reason, and I hope you continue to exploit this in future projects.