I have an idea to make these levels more interesting. We could add challenges like the ones in the main levels to our custom levels. For example...
@1N@1zAL@1g@2bAV@2I@3pAV@3D@4RAV@3W@3pAV@3W@2bAV@3D@1zAV@2I@2bAV@1g@3pAV@1g@53AV@2b@5fAV@3W@53AV@48@53AV@4k@53AV@5y@2bAV@5M@3pAV@5y@1NAV@5M@1NAV@5M@2bAV@5y@3pAV@6a@53AV Challenge: Hit all notes with the piano