diff -r 7c1d08cf6956 -r 4da0a5740b6c src/js/serializers/ldt.js
--- a/src/js/serializers/ldt.js	Fri Sep 14 10:38:04 2012 +0900
+++ b/src/js/serializers/ldt.js	Mon Sep 17 00:17:06 2012 +0900
@@ -208,7 +208,7 @@
         }
         
         if (typeof _data.meta !== "undefined" && typeof _data.meta.main_media !== "undefined" && typeof _data.meta.main_media["id-ref"] !== "undefined") {
-            _source.mainMedia = _data.meta.main_media["id-ref"];
+            _source.currentMedia = _source.getElement(_data.meta.main_media["id-ref"]);
         }
     }
 }