Is it possible however to have certain items in the legend checked and appear on default, and others that do not appear on default and must be clicked in order to be displayed? Help in this would really be a lifesaver!

may you allow me – as an up to date follow up on this topic – to refer to my blog post about dynamically toggling markers with the Google Maps JavaScript v3 API and how to apply as many custom filters, as you may need. The article can be found at: http://bexton.net/2011/06/03/the-setvisible-method-for-the-google-maps-marker-class-or-how-to-toggle-marker-icons-with-the-google-maps-v3-javascript-api/

Thank you and kind regards,
Stephan

I have found an easy solution for this issue and hope it may help. I also tested thoroughly. The fix is given below.

private var mgr:MarkerManager;

if(mgr==null)
{
mgr = new MarkerManager(map,{});
}else
{
map.clearOverlays()
mgr.clearMarkers();
map.clearOverlays()
}

NOTE: I have pasted below the complete code for viewing a sample example implemented with the fix for markermanager utitlity bug.

//*****************************************************

<![CDATA[
import mx.controls.Alert;
import com.google.maps.MapEvent;
import com.google.maps.Map;
import com.google.maps.overlays.Marker;
import com.google.maps.MapType;
import com.google.maps.LatLng;
import com.google.maps.LatLngBounds;
import com.google.maps.extras.markermanager.MarkerManager;

public var markerArr:Array = [];
private var mgr:MarkerManager;

private function createMarkers():void
{

var bounds:LatLngBounds = map.getLatLngBounds();
var southWest:LatLng = bounds.getSouthWest();
var northEast:LatLng = bounds.getNorthEast();
var lngSpan:Number = northEast.lng() – southWest.lng();
var latSpan:Number = northEast.lat() – southWest.lat();
markerArr=[]
for (var i:int = 0; i

//*****************************************************

/Pär