diff --git a/keynote_parser/codec.py b/keynote_parser/codec.py
index d8dab6b..a693d30 100644
--- a/keynote_parser/codec.py
+++ b/keynote_parser/codec.py
@@ -236,6 +236,8 @@ def to_buffer(self):
         # Each message_info as part of the header needs to be updated
         # so that its length matches the object contained within.
         for obj, message_info in zip(self.objects, self.header.message_infos):
+            if (obj.DESCRIPTOR.full_name == "TST.GroupByArchive"):
+                 obj.is_enabled = True
             try:
                 object_length = len(obj.SerializeToString())
                 provided_length = message_info.length
diff --git a/keynote_parser/mapping.py b/keynote_parser/mapping.py
index 641c7f5..d7ae7db 100644
--- a/keynote_parser/mapping.py
+++ b/keynote_parser/mapping.py
@@ -79,6 +79,8 @@ def compute_maps():
     for file in PROTO_FILES:
         for message_name in file.DESCRIPTOR.message_types_by_name:
             message_type = getattr(file, message_name)
+            for m in message_type.DESCRIPTOR.nested_types:
+                 name_class_map[m.full_name] = message_type
             name_class_map[message_type.DESCRIPTOR.full_name] = message_type
 
     id_name_map = {}