in the FORUM-> integration-> base-> lang-> [lang].php file related to your language. I've translated in FRENCH and when I but BACKSLASH for the ' character becase we have many of those in french words. The compilation doesnt get rid of the backslash when trying replacing the words in the array so it create ERRORS in classes and javascript related to that lang.
example:
'category id is not defined' => 'Identifiant catégorie n\'est pas défini',
when it compile the \' is changed to ' only so it create errors.
