Serbian translate is finis... just add/replace corect prefix en. for serbian language (sorry i dont know what prefix you use SE, SR or RS).
en_translation_4.4.31.rar
Ok, i finish translation... added to http://aslain.com/index.php?/topic/1485-translating-the-modpack-installer-language-files/page-22 You must only rename prefix for serbian language (se, sr or rs i dont know what prefix you use) ...