I was trying to display both future and archived events, but I realized that there is no option for this.
This would be useful in the case you have few events coming up and would like to also display past events.
So I added this option that you might want to include in a next release...
In wp-events.php, line 789 added:
<option value="7" <?php if($events_config['sideshow'] == "7") { echo 'selected'; } ?>>Next or archived events</option>
And in wp-events-functions.php, line 157:
} else if($events_config['sideshow'] == "7") {
$sideshow = "AND ('thetime' <= '$present' OR 'thetime' >= '$present')";
That's it :)