Just upload language files to their proper directory and activate these from this addon.

It finds those language files and extracts language code from HTML_PARAMS constant located in the main admin language file. Then guesses language code from a preedefined list (or from the language filename if the language is not in the list).

Made this one because I need several languages on each test setup and it's really boring to install these manually every time you set up a test shop. The addon has a simplified, cleaner and faster interface. It takes all data from files and only allows to customize the language name and set the default one.

Additionally I added translations for sample products, categories and pages for spanish language. If you want to add another translation you can copy the file catalog\admin\includes\languages\espanol\sample_data\translation.php to the target language folder and edit the names and descriptions. if you do so, please send me that file to be included in this addon.