Meant to be used primarily with CTGP-R's My Stuff folder. Place farm_couse.szs in the My Stuff folder in the ctgpr folder in your Wii's SD card and enable it inside the CTGP-R channel.
For Dolphin usage, decompress the game using Dolphin, replace farm_course.szs inside DATA/files/Race/Course with the one you downloaded, and recompress the game into a WBFS using Wii Backup Fusion