nprofile1qy2hwumn8ghj7un9d3shjtnyd968gmewwp6kyqpq8ylcwc4j4q8dm5tqs82yc57vd0c4t80xu9gsv742z736lhmjhrcq7ga9a8 (nprofile…a9a8) I messed about a few years ago with trying to design puzzles based on geometric packings, mainly of circles into rectangles (which I implemented as bearing balls in a wooden tray). I ran into the problem that there very often exist alternative packings that are only micro-fractionally worse: for a good puzzle one of course needs a decent gap between the intended solution and the next best packing.
(I was rather encouraged to see that Stewart Coffin's Five Fit puzzle has the same flaw.)