Most updated mods require a separate "Textures" folder. Place this in PSP -> TEXTURES on your memory stick to see the Horizon-themed graphics.
Playing community mods requires caution to protect your device and maintain smooth gameplay. Security Warning forza horizon psp iso updated
Turn off aggressive texture upscaling filters if you notice long loading screens or texture popping. A Note on Safety and Legality Most updated mods require a separate "Textures" folder