Index: lams_central/web/lams_authoring.swf
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diff -u -r15fb9094d94c2454db7bf714e52bfe09b0c278ce -rba32034dd9743c345d6d9337f61ea97ab5726cfa
Binary files differ
Index: lams_central/web/lams_authoring_library.swf
===================================================================
diff -u -r15fb9094d94c2454db7bf714e52bfe09b0c278ce -rba32034dd9743c345d6d9337f61ea97ab5726cfa
Binary files differ
Index: lams_flash/src/central/flash/org/lamsfoundation/lams/authoring/cv/PropertyInspectorControls.as
===================================================================
diff -u -r0c35a9cd829778237177b85b8174e55e5e17d060 -rba32034dd9743c345d6d9337f61ea97ab5726cfa
--- lams_flash/src/central/flash/org/lamsfoundation/lams/authoring/cv/PropertyInspectorControls.as	(.../PropertyInspectorControls.as)	(revision 0c35a9cd829778237177b85b8174e55e5e17d060)
+++ lams_flash/src/central/flash/org/lamsfoundation/lams/authoring/cv/PropertyInspectorControls.as	(.../PropertyInspectorControls.as)	(revision ba32034dd9743c345d6d9337f61ea97ab5726cfa)
@@ -1298,12 +1298,40 @@
 	 * @return  
 	 */
 	private function onGroupingMethodChange(evt:Object){
+		var groupingBy = rndGroup_radio.selection.data;
+		if (groupingBy == "num_learners") { // grouping by changed to "number of learners" check if mappings exist to previously defined groups.
+			var createGroupingUIID:Number = _canvasModel.selectedItem.activity.createGroupingUIID;
+			if (_canvasModel.getCanvas().ddm.hasBranchMappingsForGroupingUIID(createGroupingUIID)) {
+				LFMessage.showMessageConfirm(Dictionary.getValue('grp_chk_clear_branch_mappings'), Delegate.create(this, clearGroupBasedBranchMappings), Delegate.create(this, reselectGroupingByNumOfGroups));
+			} else {
+				handleGroupingMethodChange();
+			}
+		} else {
+			handleGroupingMethodChange();
+		}
+	}
+	
+	//clear branch mappings for this grouping activity
+	private function clearGroupBasedBranchMappings() {
+		var createGroupingUIID:Number = _canvasModel.selectedItem.activity.createGroupingUIID;
+		if (createGroupingUIID != null) {
+			_canvasModel.getCanvas().ddm.clearBranchMappingsByGroupingUIID(createGroupingUIID);
+		}
+			
+		handleGroupingMethodChange();
+	}
+	
+	private function reselectGroupingByNumOfGroups() {
+		numGroups_rdo.selected = true;
+		handleGroupingMethodChange();
+	}
+	
+	private function handleGroupingMethodChange() {
 		checkEnableGroupsOptions(!_canvasModel.selectedItem.activity.readOnly);
-		updateGroupingMethodData(evt);
+		updateGroupingMethodData({type:'click'});
 		setModified();
 	}
 	
-	
 	private function onScheduleOffsetChange(evt:Object){
 		
 		var startOffsetMins:Number = (days_stp.value * 60 * 24) + (hours_stp.value * 60) + mins_stp.value;