Complex sentence: The job was made somewhat easier by the work done by Sobieski and Avnet in choosing which characters from the book were going to be featured, but she found it difficult and also left the project, after writing 70 pages of the screenplay.
Split into simpler sentences: The job was made somewhat easier by the work done by Sobieski and Avnet in choosing which characters from the book were going to be featured, but she found it difficult. She too left the project, after writing 70 pages of the screenplay.