In the language file lang-en.php, this sentence a bit strange...
'_mma_forum_del_topics' => 'forum del topics',
This keyword is probably a better means:
'_mma_forum_del_topics' => 'delete forum topics',
BTW in modules/boonex/forum/integrations/base/langs/ru.php for now is:
ENGLISH language file: please UTF-8 encoding only, so use UTF-8 compliant editor only
the correct one is...
Russian language file: please UTF-8 encoding only, so use UTF-8 compliant editor only