Re-add 'Latest Post'

Good evening!

The original plugin on SM echoed the latest post by each author:

<?php $latest_post = new WP_Query( "author=$author->ID&post_count=1" );
			if (!empty($latest_post->post)){ ?>
			<p><strong>Latest Article:</strong>
			<a href="<?php echo get_permalink($latest_post->post->ID) ?>">
				<?php echo get_the_title($latest_post->post->ID) ;?>
			</a></p>
			<?php } //endif ?>

Any idea how to re-add that part back into your plugin? I’ve tried a few times but to no avail, it keeps echoing the latest post regardless of the author.

Many thanks in advance!!

http://wordpress.org/extend/plugins/simple-user-listing/