Create Wordpress Posts from XML Files

Require a light-weight php script that can read xml files and create wordpress posts (including custom fields), with the content of each xml file using XML-RPC. Must also download images (urls provided in XML file) to our server to be included in posts. The script will allow for multiple XML feeds to be submitted by multiple people (each with their own user ID). It will run by cron once per day, per XML feed, checking for updates - and will update the wordpress posts as necessary. When the script detects a new instance, it should create a new wordpress post, using the structured data inside the xml file. When the script detects a change, it should update the post to reflect the change.