v4.0.4 of SitemapXML is now available for download: https://www.zen-cart.com/downloads.php?do=file&id=367

This release contains changes associated with these GitHub issues:

#50: Use !empty instead of direct comparison to an empty string, possible NULL values.
#51: Don't include manufacturers with no products in the manufacturers' sitemap output.
#52: Correct detection of plugin-supplied additional tables, e.g. TABLE_BOX_NEWS.
#53: TABLE_BOX_NEWS, 'news_published_date' field can be null.
#54: sitemapxml_ezpages.php: Ensure that all fields for TABLE_EZPAGES are prefixed with p.