and this is pretty much the only place I could ask

4 songs have been identified while other 4 remain unknown

Tutorial/Boss Theme/The Horde - ??? Cannons and Cocktails - Hawaiian Sunrise (instrumental) Deep Trouble/Splashdown - ??? Frostbite - ??? Falling Objects - ??? The Boneyard/Citadel's Shadow - Moonlight Sonata Aperture Science/Portals for Pros/Dimension Hopping - Still Alive (remix unknown) Shadow's Citadel/Final Boss - Drawcia Sorceress remix

I would like to know if anyone knows where these songs are from, specially the boss one I've tried to ask everywhere but to no result