Older versions of Xenia had trouble rendering road textures. Ensure you are using the latest Xenia Canary build and enable mount_cache = true in the configuration file.
Reports on using with the Xenia emulator (specifically the Canary build) indicate that it is fully playable, though it requires specific manual setup as the DLC is no longer available for purchase officially. DLC Compatibility & Content forza horizon 1 dlc xenia
Monthly releases like the "September Pennzoil Pack" or "October Bondurant Pack" that added iconic vehicles. How to Install DLC on Xenia Older versions of Xenia had trouble rendering road textures