Trying to edit the .po and .mo files (restriction from the theme)

Hello guys, im trying to modified the .po and .mo files to translate mi template from english to spanish but im not able to do so. Please noete that y tried diferents plugins and editors and nothing seems to work. By using the Codestyling localalization y received the following error message and i think that is the reason why im not able to modify it please help!

Error messa: Author is using load_textdomain instead of load_theme_textdomain or load_child_theme_textdomain function. This may break behavior of WordPress, because some filters and actions won’t be executed anymore. Please contact the Author about that.