gistfile1.aw

<h1>Upcoming events:</h1>
<?php global $post;
$paged = (get_query_var('paged')) ? get_query_var('paged') : 1;
$upcoming = tribe_get_events( array('eventDisplay'=>'past', 'posts_per_page'=>1,'paged' => get_query_var('page')) );
foreach($upcoming as $post) : setup_postdata($post);?>
<div class="single-event">
<div class="title"><a href="<?php the_permalink() ?>" rel="bookmark">
<?php the_title(); ?>
</a> </div>
<?php endforeach; ?>
<?php if(function_exists('wp_pagenavi')) { // if PageNavi is activated ?>
<?php wp_pagenavi(); }

/**
 * above is the original untouched code
 * below is the better code (and it works!)
 * the main difference is the use of WP_Query instead of tribe_get_events
 * doing so is more efficient and ensures compatibility with WPPageNavi
 * @see @link http://scribu.net/wordpress/wp-pagenavi/wpn-2-74.html for more details
 */

$paged = ( get_query_var('paged') ) ? get_query_var('paged') : 1;
$upcoming = new WP_Query();
$upcoming->query( array('post_type'=> 'tribe_events', 'eventDisplay' => 'past', 'posts_per_page' => 1, 'paged' => $paged) );
if ($upcoming->have_posts()) :
	while ($upcoming->have_posts()) :
		$upcoming->the_post();
?>
		<div class="single-event">
		<div class="title"><a href="<?php the_permalink() ?>" rel="bookmark"><?php the_title(); ?></a></div>
<?php
	endwhile;
	wp_pagenavi( array( 'query' => $upcoming ) );
endif;
wp_reset_query();
?>

Shouldn't it be 'eventDisplay' => 'upcoming' for upcoming events instead of 'past'?

Depends on what you are trying to do with it. In this case, the user wanted to display past events.