User creative common music score.
another site playalongpiano.com uses musescore's creative common score to get music on the fly. If its there and its un-copyrighted it can be played in the site. This will bump up your library without adding in extra score all the time
The site doesn't seem to be loading the scores from musescore directly. Whether they load it indirectly through some service or store the files somewhere manually - it's definitely not automatic / free.
The scores seem to be in a musescore format, which isn't MIDI. And Midiano currently only accepts MIDI files. I've played with the thought of also allowing different formats but that would be quite a large task and I'm not currently planning on doing that.
User creative common music score. another site playalongpiano.com uses musescore's creative common score to get music on the fly. If its there and its un-copyrighted it can be played in the site. This will bump up your library without adding in extra score all the time