Lightmotion.net (they do fire and light shows) have an interesting use of the plugin widget.   Gerald has used two widgets with different parameters to show “past events” and “future events” that appear to be grouped.   The plugin does allow for past and future events to be styled differently, this would not achieve the grouping. I assume that what he has done is have widgets with following parameters:

1. widget past (showing events for last 20 days): startoffset=-20 days=20
2. widget future (showing events for last 20 days): days=20

If you want to do something like this yourself, one thing to bear in mind is that one must balance the number of events with your event frequency and the timeperiod to ensure that the most recent ‘past’ events will show.  Use events=x in the shortcode to override the default number of events (60? or 30? I forget!)