IMSLP Forums

I just recently came across the works of Leo Ornstein, and they seem to have all been released under the Performance Restricted Attribution Non-commercial No Derivatives 1.0 license, which I am not familiar with. Even after reading various forum posts, it's still not completely clear to me. https://imslpforums.org/viewtopic.php?f ... 1.0#p25045

Are even non-commercial performances of music licensed in this way are restricted?

Thank you for time.