     private static function createOSMLayer(layerCreationProperties:LayerCreationProperties):OpenStreetMapLayer
     {
         var osmLayer:OpenStreetMapLayer = new OpenStreetMapLayer();
-        osmLayer.copyright = layerCreationProperties.copyright;
         osmLayer.alpha = layerCreationProperties.alpha;
         osmLayer.id = layerCreationProperties.label;
         osmLayer.name = layerCreationProperties.label;
         osmLayer.visible = layerCreationProperties.visible;
         osmLayer.showInLegend = layerCreationProperties.showInLegend;
+        if (layerCreationProperties.copyright != null)
+        {
+            osmLayer.copyright = layerCreationProperties.copyright;
+        }
         if (!isNaN(layerCreationProperties.minScale))
         {
             osmLayer.minScale = layerCreationProperties.minScale;

        imgLayer.useMapTime = layerCreationProperties.useMapTime;
        imgLayer.disableClientCaching = layerCreationProperties.disableClientCaching;
        imgLayer.showInLegend = layerCreationProperties.showInLegend;
        if (layerCreationProperties.imageFormat)
        {
            imgLayer.imageFormat = layerCreationProperties.imageFormat;

    private static function createBingLayer(layerCreationProperties:LayerCreationProperties):VETiledLayer
    {
        var veTiledLayer:VETiledLayer = new VETiledLayer();
        veTiledLayer.id = layerCreationProperties.label;
        veTiledLayer.name = layerCreationProperties.label;
        veTiledLayer.key = layerCreationProperties.bingMapKey;
        veTiledLayer.visible = layerCreationProperties.visible;
        veTiledLayer.alpha = layerCreationProperties.alpha;
        veTiledLayer.showInLegend = layerCreationProperties.showInLegend;
        if (layerCreationProperties.copyright != null)
        {
            veTiledLayer.copyright = layerCreationProperties.copyright;
        }
        if (layerCreationProperties.style)
        {
            veTiledLayer.mapStyle = layerCreationProperties.style;
