CB doesn't currently support Joomlas language filter plugin (responsible for multi-lingual menus, etc..). My guess is you get the 404 because CB is pulling the Itemid of the English menu link and by Joomlas accord that menu link doesn't exist except when using English.
forge.joomlapolis.com/issues/3070
This is scheduled for implementation in CB 1.8 Stable (note 1.8 RC scheduled for today may not have this implemented yet).