Wow, I had a lot of fun with this! My favorite part of this game was how effective it was at having each level keep escalating the challenge by introducing either new mechanics or providing fresh combinations or complications with existing mechanics. It was just so addicting as it never allowed the pace to slow down at any point: every time you think you've seen it all, the next level steps it up! I also just really liked the concept in general and with such a good execution, I enjoyed my time with it.
In terms of feedback, the game was a bit wonky at times with physics. Nothing drastic, but occasionally there would be stuff like two green blocks side by side in a pathway clearly big enough for the both of them, but only one of them makes it through while the other gets caught on something for no reason. Also I felt like, while the options menu had great buttons with highlights and such, the main menu screen was lacking in this as the buttons were very basic and unpolished. Finally, I did feel like the game could've introduced the controls a bit better: perhaps put some left/right arrows on the side of the screen that glow when you mouse over them, indicating where to click to rotate the board.