I gave up on my first play through of Chrono Trigger because I couldn't figure out how to progress in the future world. Didn't realize that the clouds in the dome were supposed to be transparent and not something that I need to trigger a different event to clear up.

My first playthrough of Chrono Trigger was stopped cold because my PC couldn't send enough simultaneous keypresses to unlock a door.

Yeah I'm not sure how I figured that trick out, probably just monkey mashing buttons at some point, then I figured out SNES graphics were layers and it was a lot of fun switching the various layers on+off. And hey that turned out to be useful!