Yo, recently I've been having trouble getting textures to...

Yo, recently I've been having trouble getting textures to show up in some HL2 community mods on Steam (Requiem of Science, Artic Adventures: Episodes, and Amalgam) Can someone help me on this? Is it because I don't own Counter Strike Source, or is it just not downloading right (Textures missing include but are not limited to, Skybox, Floors, Doors, etc.) Please comment responces