diff --git a/mocha-common/compilers/yaml2mcl/Program.py b/mocha-common/compilers/yaml2mcl/Program.py
index 766d70a..68d75ed 100644
--- a/mocha-common/compilers/yaml2mcl/Program.py
+++ b/mocha-common/compilers/yaml2mcl/Program.py
@@ -78,6 +78,8 @@ class Yaml2Mcl:
 		yl = YAMLLibraryParser(manager)
 
 		# before we load any files, load entity definitions from referenced libraries
+		libraryRefGuids = [ ]
+
 		for libraryRef in libraryReferences:
 			from mocha.library.mcx.dataformats import McxDataFormat
 			from mocha.library.mcx.objectmodels import McxObjectModel
@@ -88,6 +90,8 @@ class Yaml2Mcl:
 			df.load_internal(om, f)
 			f.close()
 
+			libraryRefGuids.append(om.get_guid())
+
 			print ("loading entity definitions from library reference '" + libraryRef + "'")
 
 			for (k, v) in om.get_entity_definitions():
@@ -103,6 +107,7 @@ class Yaml2Mcl:
 			for key in tdfs:
 				yl.register_template(key, tdfs[key], True)
 			
+		manager.library_reference_guids = libraryRefGuids
 
 		for filename in filenames:
 			if not os.path.isdir(filename):
diff --git a/mocha-common/compilers/yaml2mcl/mocha/library/manager/MemoryLibraryManager.py b/mocha-common/compilers/yaml2mcl/mocha/library/manager/MemoryLibraryManager.py
index 5116029..8044b86 100644
--- a/mocha-common/compilers/yaml2mcl/mocha/library/manager/MemoryLibraryManager.py
+++ b/mocha-common/compilers/yaml2mcl/mocha/library/manager/MemoryLibraryManager.py
@@ -30,6 +30,8 @@ class MemoryLibraryManager (MochaLibraryManager):
 		self.attribute_ops = [ ]
 		self.relationship_ops = [ ]
 
+		self.library_reference_guids = [ ]
+
 	def process_attribute_ops(self, ops):
 		self.attribute_ops.extend(ops)
 			
@@ -84,7 +86,7 @@ class MemoryLibraryManager (MochaLibraryManager):
 		# *** SECOND PASS ***
 
 		# first, go through and load all the instances GUIDs
-		refs = [ ]
+		refs_db = [ ]
 		insts = [ ]
 		atts = [ ]
 		rels = [ ]
@@ -138,6 +140,9 @@ class MemoryLibraryManager (MochaLibraryManager):
 			print(dump)
 			templates_db[str(key2)] = dump
 
+		for r in self.library_reference_guids:
+			refs_db.append(r)
+
 		from .sectionfile import SectionFile, Section, GuidSection, InstancesSection, AttributesSection, RelationshipsSection, StringTableSection, ResourcesSection, DefinitionsSection, TemplatesSection
 		f = SectionFile("MCX!", 2.0, 15)
 		f.open(self.filename)
@@ -150,6 +155,7 @@ class MemoryLibraryManager (MochaLibraryManager):
 		f.sections.append(ResourcesSection("Resources", rsrc_db))
 		f.sections.append(DefinitionsSection(defs_db))
 		f.sections.append(TemplatesSection(templates_db))
+		f.sections.append(GuidSection("LibraryRefs", refs_db))
 
 		f.save()
 
diff --git a/mocha-common/compilers/yaml2mcl/mocha/library/mcx/dataformats/McxDataFormat.py b/mocha-common/compilers/yaml2mcl/mocha/library/mcx/dataformats/McxDataFormat.py
index 65e7309..03fa91f 100644
--- a/mocha-common/compilers/yaml2mcl/mocha/library/mcx/dataformats/McxDataFormat.py
+++ b/mocha-common/compilers/yaml2mcl/mocha/library/mcx/dataformats/McxDataFormat.py
@@ -49,6 +49,7 @@ class McxDataFormat (DataFormat):
 		flags = r.read_int32()
 		section_count = r.read_int32()
 		guid = r.read_guid()
+		object_model.set_guid(guid)
 
 		sections = [ ]
 
@@ -68,17 +69,20 @@ class McxDataFormat (DataFormat):
 
 		for (section_name, offset, length, length2, itemcount) in sections:
 			if section_name == 'GUIDTable':
-				print("mcx: reading GUID table")
+				print("mcx: reading GUID table (offset %s, length %s, count %s)" % (offset, length, itemcount))
 				r.get_stream().seek(offset)
 				for i in range(0, itemcount):
-					gids.append(r.read_guid())
+					gid = r.read_guid()
+					gids.append(gid)
+					print(gid)
+				print (str(len(gids)) + " GUIDs loaded")
 			elif section_name == 'StringTable':
-				print("mcx: reading string table")
+				print("mcx: reading string table (offset %s, length %s, count %s)" % (offset, length, itemcount))
 				r.get_stream().seek(offset)
 				for i in range(0, itemcount):
 					strs.append(r.read_terminatedstring())
 			elif section_name == 'Defs':
-				print("mcx: reading definitions")
+				print("mcx: reading definitions (offset %s, length %s, count %s)" % (offset, length, itemcount))
 				r.get_stream().seek(offset)
 				for i in range(0, itemcount):
 					key = r.read_terminatedstring()
@@ -87,13 +91,19 @@ class McxDataFormat (DataFormat):
 
 		for (section_name, offset, length, length2, itemcount) in sections:
 			if section_name == 'Instances':
-				print("mcx: reading instances")
+				print("mcx: reading instances at offset " + str(offset))
 				r.get_stream().seek(offset)
 				for i in range(0, itemcount):
 					cgidi = r.read_int32()
 					cgid = gids[cgidi]
 					igidi = r.read_int32()
-					igid = gids[igidi]
+
+					igid = None
+					if igidi >= 0 and igidi < len(gids):
+						igid = gids[igidi]
+					else:
+						print("not found igid at index " + str(igidi))
+
 					ckey = r.read_int32()
 					ikey = r.read_int32()
 
diff --git a/mocha-common/compilers/yaml2mcl/mocha/library/mcx/objectmodels/McxObjectModel.py b/mocha-common/compilers/yaml2mcl/mocha/library/mcx/objectmodels/McxObjectModel.py
index 6119efe..361117e 100644
--- a/mocha-common/compilers/yaml2mcl/mocha/library/mcx/objectmodels/McxObjectModel.py
+++ b/mocha-common/compilers/yaml2mcl/mocha/library/mcx/objectmodels/McxObjectModel.py
@@ -16,6 +16,12 @@ class McxObjectModel (ObjectModel):
 		self.__entityDefinitionsValues = dict()
 
 		self.template_definitions = dict()
+		self.__guid = None
+
+	def get_guid(self):
+		return self.__guid
+	def set_guid(self, guid):
+		self.__guid = guid
 
 	def get_instances(self) -> list[McxInstance]:
 		return self._instances