Olso look if any mods are updated and the developer have at least a instruction how to install it. Though there are very good moddifications of games around out there in this huge universe of coding, I suggest try to guugle around to maby understand that your game might be totaly deleted if you are not aware with the risks. That means that code will be overwritten and or deleted by files other then recommended, even if its is 'just visiuals'. Yes, mods can mess with gamefiles simply because they are 'mods' wich mean a modification of some files to obtain and or circumstance basic files originaly written by the developers.