For me duck kept either falling through the bottom or being too big to fit, spent some time to get it just right. Maybe put floor under the gap? Also, why is the left gap narrower than the right one on the way to the exit? thought it had something to do with the solution before noticing the duck changing size.
Viewing post in I need help on level 4 (level order changed - this is now LVL 6)
For me duck kept either falling through the bottom or being too big to fit, spent some time to get it just right. Maybe put floor under the gap?
So this isn't actually the intended way of doing it. I put the floor gap there to stop people trying to do it this way :D So yeah there's a different solution.