This snippets allows EE events/venues to use the feature image as the 'header image' within the Alone theme.

alone_theme_add_header_image_to_ee_cpts.php

<?php // Please do not include the opening PHP tag if you already have one.

function alone_theme_add_header_image_to_ee_cpts($post_id, $post, $update) {
    if (isset($_REQUEST['action'])
        && (
            $_REQUEST['action'] === 'restore'
            || $_REQUEST['action'] === 'trash'
        ) 
        && strpos($post->post_type, 'espresso_')
    ) {
        return;
    }

    if (! function_exists('fw_set_db_post_option')) {
        return;
    }

    $feature_image_id = get_post_thumbnail_id($post);
    $feature_image_url = get_the_post_thumbnail_url($post);

    //$default_options = fw()->theme->get_post_options('post');
    //$post_options = fw_get_options_values_from_input($default_options);

    $post_options['header_image'] = array(
        'attachment_id' => $feature_image_id,
        'url' => str_replace( array( 'http:', 'https:' ), '', $feature_image_url )
    );

    fw_set_db_post_option(
        $post_id,
        null,
        $post_options
    );
}
add_action('save_post', 'alone_theme_add_header_image_to_ee_cpts', 10, 3 );