Chouby on "Polylang and latest Pytheas theme"

Your wpml-config.xml file is correct if the options are existing.
Did you fill the values in the theme options?
Did you check the file permissions?

In Pytheas 1.0, I found all the relevant informations in the file options.php in the theme directory. It seems that you found this information since you have new / different options.
Almost on top, I found the lines:

function optionsframework_option_name() {
    $optionsframework_settings = get_option('optionsframework');
    $optionsframework_settings['id'] = 'options_wpex_themes';
    update_option('optionsframework', $optionsframework_settings);
}

To obtain the name of the general option 'options_wpex_themes' where all theme options are stored. Is it still the same?