I've choosen the shutter marker because it seemed like the easiest one to notice when to press, while I was choosing from the different markers on the list. I will try looking at it again, maybe now it will be easier to notice when to press, also during the gameplay afterwards. Somehow even if I know theoretically how to read it, I'm still not 100% sure whether I really know it. I try to hit the marker (shutter) at the moment it closes. Today, during my play I was paying attention and played my songs more carefully then normally, so I got rewarded with better scores. However, I cannot tell for sure whether it was thanks to reading of a marker or listening to the beat. Probably both

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If you don't have e-amusement, you cannot unlock songs. Are all the songs already unlocked at your place? Or can you only play the songs that are on the list from the beginning?