Overall very interesting concept.
I like how you combined that old planko concept with the color mixer.
It would be nice if the movement of the bucket were telecasted or announced a little louder because it's movements can go unnoticed.
Once you go overboard in a particular color it would be nice, I think to have the block get incinerated or something so the player doesn't go too far in the wrong direction or waste any further time...
Another thought as far as input goes is the order of events goes from right to left which may be a little counter-intuitive. Maybe try putting the color droppers on the left and the drop button on the right.
Music is nice, and all in all a nice game. I definitely had some fun playing :)