The basic widget HTML markup to display one element looks the following way:

<div class="google-map-container" data-center='9870 St Vincent Place, Glasgow, DC 45 Fr 45.'>
  <div class="google-map"></div>
  <ul class="google-map-markers">
    <li data-location="9870 St Vincent Place, Glasgow, DC 45 Fr 45." data-description="9870 St Vincent Place, Glasgow" data-icon="images/gmap_marker.png" data-icon-active="images/gmap_marker_active.png"></li>
    <li data-location="2-1 Drumilaw Rd, Rutherglen, Glasgow Metropolitan Area G73 4NU, Greatbritain" data-description="2-1 Drumilaw Rd, Rutherglen, Glasgow Metropolitan Area" data-icon="images/gmap_marker.png" data-icon-active="images/gmap_marker_active.png"></li>
  </ul>
</div>

To change style of the map use data attribute data-style=' ... '.

<div class="google-map-container" data-center=' ... ' data-style=' ... ' >
  ...
</div>