Event Countdown Shortcode?

I can't seem to get the event countdown shortcode to display. I've set up one event, for September 1–2, 2014. (Yes, 2014.) When I use only


the shortcode returns "Closed," and when I qualify it further with

[event_countdown format="dHMS" goto="http://example.com" class="countdown-class" type="flip" size="70" add="-120" expired="Too late!"]

(copied & edited from the Event Settings page), I get nothing at all. Has anyone else dealt with this?