Yes, Well You need to read this
The MO is the end of the line. The MO provides full support for a given language. To install French language support, a user would place fr.mo into the wp-includes/languages directory of his WordPress installation, and change the define('WPLANG', ''); in his wp-config.php file to define('WPLANG', 'fr');.
Same thing for other languages: he would use the MO file corresponding to his language and replace the country-code in the wp-config.php file with the one that matches the MO : 'hi', 'es_ES', 'pt_BR'.
BUT!!! indeed, there is no /wp-includes/languages directory in there So I don't know what to do either atm. You, need to complile the PO to a MO. But where to put the files? no Idea