Custom fields not appearing in metadata

Hello.

Your plugin should be an excellent bridge for something I’m trying to accomplish, but it’s not acting as expected.

On one end, I’m using a plugin for custom taxonomies. On the other end, I’m using another plugin that allows me to generate filtered RSS feeds right through the feed URL for the purpose of generating newsletters. That plugin allows filtering by metadata, and when I create custom fields using WP’s native option, they appear in the metadata.

However, although your plugin perfectly captures my custom taxonomies, your custom fields don’t appear in the metadata on the other end. Any ideas what might be going on?

Thank you for your time,
Justin