One sindax error.
File:
includes/functions/extrafunctions/cat_filter.php

Line: 76
from
INNER JOIN categories_description c
to
INNER JOIN ".TABLE_CATEGORIES_DESCRIPTION." cd

Line: 80
from
INNER JOIN categories as c
to
INNER JOIN ".TABLE_CATEGORIES." as c


For me, in this new version all filtering with multilangual installation working fine exept the main_page=products_new

Congratulation Gerome :)