We discovered (and resolved) a local US firewall issue with this plugin.
In this file:
google-maps-widget/google-maps-widget.php
We needed to change the Google maps website being called from the UK to the US. Here is the code before and after the change:
$map_url = 'http://maps.google.co.uk/maps?hl=en&ie=utf8&output=embed&iwloc=' . $iwloc . '&iwd=1&mrt=loc&t=' . $widget['type'] . '&q=' . urlencode($widget['address']) . '&z=' . urlencode($widget['zoom']) . '';
$map_url = 'http://maps.google.com/maps?hl=en&ie=utf8&output=embed&iwloc=' . $iwloc . '&iwd=1&mrt=loc&t=' . $widget['type'] . '&q=' . urlencode($widget['address']) . '&z=' . urlencode($widget['zoom']) . '';
