In RHEM 4 I was stuck at the place where you had to put in the block configuration on the "LT" panel. I was wandering around for hours looking for a clue, anything, then just as I was about to give up I went over to
Spoiler:those pictures it looked that a child had painted on and saw the cherries were over the correct dots
It was a definite "aha" moment because I had already used them for another clue and didn't expect there would be anything else there to find. I felt stupid for not noticing it earlier.