If the keys for changing the robots weren't the same ones for moving then it would be much smoother (many times I pressed the space bar, but because I took too long the current robot moves instead of switching)
The levels that used blocks that could move in only one direction seemed much harder than the levels that came after they, maybe these should be the last ones?
Hey andre_timpa! Thanks for the feedback! Noted. Getting the difficulty curve right has been very difficult!