I really liked this demo, I can't compare it to the last one because I haven't played it but I saw your videos and the version 2 seems so much better than the first.
Here is some points that I think can be improved :
- As others said, the polarity change on the keyboard is weird, the mouse makes more sense because you throw the magnet with it
- When I encountered the platforms on the following screen, I was expecting to press the S key to go down
- On level 6, there is a little gap between the blue cube when it is up so I threw the magnet in there and when the blue cube went down, it prevented the cube from pressing the button, solving the puzzle ^^'
- The robot is too slow, maybe add a walk/run button
- The level 3 is way too easy
- I found it weird that the robot is attracted with the magnet on straight attractors but not on cornered ones