Hi!
I'm not sure, that it's a problem of Polylang, but I've got error each time when I creating new language version of page on site with custom theme.
Fatal error: Call to undefined method Polylang_Nav_Menu::get_post_language() in /home/users1/r/renovatio/domains/renovatio.ru/wp-content/plugins/polylang/include/nav-menu.php on line 147
After F5 in browser window I can see my new language version of page.
It happens in theme FloZo (http://www.flyerzone.co.uk/blog/download-the-free-flozo-wordpress-theme/). By default menus from this theme don't loaded in Polylang at all, so I add string to function.php of theme, to fix it:
register_nav_menu( 'primary', __( 'Primary Menu', 'flozo' ) );
Sorry, I don't PHP-coder and not sure where's a problem.