Yeah, sorry. I guess I should have followed up on this.
I ended up writing some code that reads the TV value and re-orders the date so that strtotime() could be used:
$year = substr($event_date,6,4);
$month = substr($event_date,3,2);
$day = substr($event_date,0,2);
$time = substr($event_date,11,8);
$widget_date = strtotime($year . '-' . $month . '-' . $day . ' ' . $time); // ...and Bob's your uncle!
The TV’s value gets put into $event_date by a function I wrote myself as couldn’t get the MODx function to work. But it does work (when I tried it again later).
Hope that helps.