 			Admin.service.updateEntity(id, diff);
 			invalidate(id);
         }
-        public function add_category(label:String, parentId:int, index:int):void
+        public function add_category(title:String, parentId:int, index:int):void
         {
 			var type:int = parentId == ROOT_ID ? EntityType.HIERARCHY : EntityType.CATEGORY;
             var em:EntityMetadata = new EntityMetadata();
-			em.publicMetadata[ColumnMetadata.TITLE] = label;
+			em.publicMetadata[ColumnMetadata.TITLE] = title;
 			Admin.service.newEntity(type, em, parentId, index);
 			invalidate(parentId);
         }
         public function delete_entity(id:int):void
         {
             /* Entity deletion should usually impact root, so we'll invalidate root's cache entry and refetch. */
-			delete_later[id] = true;
+			idsToDelete[id] = true;
 			invalidate(id, true);
         }
         public function add_child(parent_id:int, child_id:int, index:int):void
         {
-			if (parent_id == ROOT_ID && delete_later[child_id])
+			if (parent_id == ROOT_ID && idsToDelete[child_id])
 			{
 				// prevent hierarchy-dragged-to-root from removing the hierarchy
-				delete delete_later[child_id];
+				delete idsToDelete[child_id];
 				return;
 			}
 			Admin.service.addParentChildRelationship(parent_id, child_id, index);

			}
			if (ids.length > 0)
			{
				cache_dirty = {};
				addAsyncResponder(Admin.service.getEntitiesById(ids), getEntityHandler, null, ids);
			}
        }

			// delete marked entities
			var deleted:Boolean = false;
			var idsToRemove:Array = [];
			for (id in idsToDelete)
				idsToRemove.push(id);
			
			if (idsToRemove.length)
			{
				addAsyncResponder(Admin.service.removeEntities(idsToRemove), handleRemoveEntities);
				idsToDelete = {};
			}
			
			// request invalidated entities
			var ids:Array = [];
			for (id in idsToFetch)
			{
				// when requesting root, also request data table list
				if (id == ROOT_ID)
				{
					delete idsToFetch[id];
					addAsyncResponder(Admin.service.getEntityHierarchyInfo(EntityType.TABLE), handleEntityHierarchyInfo, null, EntityType.TABLE);
					addAsyncResponder(Admin.service.getEntityHierarchyInfo(EntityType.HIERARCHY), handleEntityHierarchyInfo, null, EntityType.HIERARCHY);
				}
