Update 5/27

 Thanks to L.O. or Val A, we have some more info about the Unidentified Tracks. First off, Unknown Tracks 4, 8, and 9, are officially identified as In Sombre Mood by Wilfred Burns (APM), Disaster & Desolation by Hubert Clifford (Chappell), and Mysterious Background by Vlastimil Hala (Chappell/IntervoX) respectively. Second, thanks to a secret folder I gained access to from him, we finally have all of the unidentified tracks without all of the dialogue in the way, making it much easier. Third, after listening to Unidentified tracks 3 and 5, I realized that it is possible that they are the same track, so keep that in mind.

Update 3/31

I managed to identify both The Haunted Piano and Motif for Murder.

Update 5/24

Val R from YouTube identified Of Love and Destiny by Leighton Lucas for Unknown Track 7! He apparently also knows how to get the entire series without voices, but he deleted the comment before we even found out how.