By editing PROLOGUE.rpf (specifically the northyankton.ymap files), modders have unlocked the entire snowy state for free-roam. However, errors occur when users try to merge these modded PROLOGUE.rpf files with newer game versions (e.g., the Los Santos Summer Special update). If you are attempting the "North Yankton glitch" or mod, ensure you are using a PROLOGUE.rpf built for your specific game patch (v1.0.xxx).