Onili - Games (scene: Derek taunts Paige in the hallway with his basketball)

Bedouin Soundclash - Brutal Hearts (scene: Paige puts Derek's music skills to test in the music room)

Oliver Tank - The Last Time (scene: Paige and Derek share a stolen moment at the distillery)

Deaf Joe - Joanna (scene: Derek tries to distract Paige while playing the cello)

Mozart Requiem Kv 626 - 8 Sequentia Lacrimosa by RSO Ljubljana & Vladislav Tscherneshenko 

Page is playing on the cello. 

Ellen's Chants, D. 839: III. Ave Maria by The Budapest Strings & Bela Banfalvi 

The piece Page is practising while Derek is distracting her. Also at the end when Derek is alone in the distillery. 

Miserere by The Tallis Scholars & Peter Phillips

when Derek puts Paige out of her misery. 

Requiem, Op. 48: Introit Et Kyrie by Lisa Beckley, Colm Carey, Nicholas Gedge, Oxford Schola Cantorum, Jeremy Summerly & Oxford Camerata 

When Young Derek takes Paige out of her misery.