Complex sentence: In addition to the songs already written by Shaffer, Arvizu and Luzier, Davis wrote eleven songs in less than five days shortly after, Davis recorded demos of his songs with guitar and bass recorded by himself over a programmed drum beat.
Split into simpler sentences: In addition to the songs already written by Shaffer, Arvizu and Luzier, Davis wrote eleven songs in less than five days. He recorded demos of his songs, playing guitar and bass himself over a programmed drum beat.