Try closing your game and restarting it and making sure that you saved your complete preset and all of its individual files into one of the (Preset_1-Preset_12) folders in your "My_Presets" folder. If you saved your preset correctly and made sure that all the body parts are jpeg image, and the mane png etc, and material file is there it should appear as one of the loadable presets in the Preset Maker.