See this post for a full description.
V2
Fixes:
The url of the xap is still relative but now it is relative to the host so if your blog is in a subfolder you have to prefix the default upload folder with the subfolder.
E.g., if your wordpress site is here: http://www.blahblah.com/publications the default folder in the plugin settings has to be: /publications/wp-content/uploads
V1
First release