Complex sentence: In the process of preparing a performing edition of the score, Woodward consulted Rosemary Brown, who was a prominent spiritualist, known for mediumship with dead composers and for transcribing musical works they dictated.
Split into simpler sentences: In the process of preparing a performing edition of the score, Woodward consulted Rosemary Brown. Brown was a prominent spiritualist, known for mediumship with dead composers and for transcribing musical works they dictated.