There are a fair number of games targeted for 50Hz that reliably crash when played at 60, so I'm not at all surprised that the opposite is true. In the case of 50 > 60 my understanding is that the lack of VBLANK time at 60Hz (and 525 lines) is often the culprit; no idea what would cause the reverse issue, but I'm sure it's something arcane and hard to debug.
Can it also be a vblank issue in my case? In 50hz the title screen is blank, music plays, but i can't press any button. If I switch it to 60hz, the menu appears, I can start the game and switch it back to 50hz and it works.