Posted this already in the themes forum, but I think that may have been the wrong place to put it so:
I've tried installing the downloads box plugin (http://wordpress.org/extend/plugins/downloads-box/) on a test site I'm running locally. Dragged the widget to the sidebar (there are two available) and entered the relevent details, but it does not appear on the site.
Seen other threads advising people to check that the dynamic_sidebar() function is present in functions.php. It is on mine, it sets up the two sidebars mentioned above.
Also saw a thread advising to check sidebar.php for a dynamic_sidebar() function. All that is in there are two div tags with code detailing a menu consisting of links of categories. So I had a pop at lashing some code in there (though I haven't a notion about PHP) :
<ul id="sidebar"> <?php dynamic_sidebar( 'Test Sidebar' ); ?> </ul>
That made absolutley no difference at all! If anyone has an idea of where I'm going wrong I'd appreciate it.