Ok, lvl1 puzzle 3 has multiple options: the blue dot centre of the 3rd square from the left, 3.5 squares from the bottom (and the two reds on a / diagonal with it) have two possible configurations, which do not affect the area outside of those three dots.
Really quite good up until around level 23. At that point I ran out of things to do and was essentially just in a corner spamming outwards, only having to move occasionally.