Very cute little game!
Really like the spin on the "haunted cartridge" trope, from a more loving standpoint with the idea of fixing a broken forgotten game.
Like the other commenters, I had a few gameplay issues, particularly with the dispaly/resolution. I ran this on a 4k monitor and had to fiddle with the size of the game window quite a bit to both be able to read the text and see the sprites. At the end the choices to fix or throw away the game completely overlapped one another, and selecting one was very difficult. At the end, choosing to "fix the game" caused the screen to continually fade to black then fade back in, with nothing new happening, so I don't know if there's any content beyond that point. I also experienced a few collision issues, but those were more minor.
The game also deviated quite a bit from GB restrictions, but you know that by now. For what it is, I really liked the tone and delivery of the narrative, and found that to be the clear strong suit of this project. The core mechanics could use some work to make the moment to memento a bit more engaging, and maybe drive the point of fighting against the cartridge's corruption a bit harder.
Good work here, keep it up!