A shortcode to render an RSS feed in a post/page
Yes, add either show_summary=1, show_date=1 or show_author=1 to the tag.
It seems this is an issue with the RSS code in WordPress, rather than with my plugin.
Make sure your url is valid, contains no spaces, and is properly html-encoded(if you use the HTML editor).
A temporary solutions is to pass your feed through FeedBurner, which does seem to work.