diff --git a/repository/OpenPonk-Core/OPDirectionalRelationshipController.class.st b/repository/OpenPonk-Core/OPDirectionalRelationshipController.class.st
index be4bb63c..062b32c3 100644
--- a/repository/OpenPonk-Core/OPDirectionalRelationshipController.class.st
+++ b/repository/OpenPonk-Core/OPDirectionalRelationshipController.class.st
@@ -19,6 +19,8 @@ Class {
 OPDirectionalRelationshipController >> createDiagramElement [
 
 	super createDiagramElement.
+	self ensureSourceIn: diagramController.
+	self ensureTargetIn: diagramController.
 	^ self diagramElement
 		  source: self source ensureDiagramElement;
 		  target: self target ensureDiagramElement;
@@ -52,14 +54,6 @@ OPDirectionalRelationshipController >> edgeBuilder [
 		'Depracated without replacement - use Roassal directly or define own figures'
 ]
 
-{ #category : 'construction' }
-OPDirectionalRelationshipController >> ensureShownDependenciesInDiagram: aDiagramController [
-
-	self ensureSourceIn: aDiagramController.
-	self ensureTargetIn: aDiagramController.
-	super ensureShownDependenciesInDiagram: aDiagramController
-]
-
 { #category : 'accessing' }
 OPDirectionalRelationshipController >> ensureSourceIn: aDiagramController [
 
@@ -122,6 +116,14 @@ OPDirectionalRelationshipController >> renderSimplified [
 	diagramElement := self diagramElementClass renderSimplifiedForController: self.
 ]
 
+{ #category : 'construction' }
+OPDirectionalRelationshipController >> showWithoutDependentInDiagram: aDiagramController [
+
+	self ensureSourceIn: aDiagramController.
+	self ensureTargetIn: aDiagramController.
+	^ super showWithoutDependentInDiagram: aDiagramController
+]
+
 { #category : 'accessing' }
 OPDirectionalRelationshipController >> source [
 
diff --git a/repository/OpenPonk-Core/OPExamplePersistenceTest.class.st b/repository/OpenPonk-Core/OPExamplePersistenceTest.class.st
new file mode 100644
index 00000000..a0993e89
--- /dev/null
+++ b/repository/OpenPonk-Core/OPExamplePersistenceTest.class.st
@@ -0,0 +1,79 @@
+Class {
+	#name : 'OPExamplePersistenceTest',
+	#superclass : 'TestCase',
+	#instVars : [
+		'file',
+		'sourceWorkbench',
+		'targetWorkbench'
+	],
+	#category : 'OpenPonk-Core-Tests',
+	#package : 'OpenPonk-Core',
+	#tag : 'Tests'
+}
+
+{ #category : 'testing' }
+OPExamplePersistenceTest class >> isAbstract [
+
+	^ self = OPExamplePersistenceTest
+]
+
+{ #category : 'hooks' }
+OPExamplePersistenceTest >> createExampleModel [
+
+	^ self subclassResponsibility
+]
+
+{ #category : 'running' }
+OPExamplePersistenceTest >> setUp [
+
+	super setUp.
+	file := FileSystem memory root / 'example-persistence-test.opp'.
+	file ensureDelete
+]
+
+{ #category : 'running' }
+OPExamplePersistenceTest >> tearDown [
+
+	sourceWorkbench ifNotNil: [ :workbench |
+		workbench application closeAllWindows.
+		sourceWorkbench := nil ].
+	targetWorkbench ifNotNil: [ :workbench |
+		workbench application closeAllWindows.
+		targetWorkbench := nil ].
+	file ifNotNil: [
+		file ensureDelete.
+		file := nil ].
+	Smalltalk garbageCollect.
+	super tearDown
+]
+
+{ #category : 'tests' }
+OPExamplePersistenceTest >> testSaveAndLoad [
+
+	| sourceModel sourceProject sourceEditor sourceCanvas sourceProjectController sourceShapes targetProject targetEditor targetCanvas targetShapes |
+	sourceModel := self createExampleModel.
+	sourceProject := OPProject new
+		                 name: 'TestProject';
+		                 addModel: sourceModel;
+		                 yourself.
+	sourceWorkbench := sourceProject open.
+	sourceWorkbench showAllElementsInAllDiagrams.
+	sourceEditor := sourceWorkbench focusedEditor.
+	sourceCanvas := sourceEditor canvasPresenter canvas.
+	sourceShapes := sourceCanvas shapes
+		                collect: [ :each | each class ]
+		                as: Bag.
+	self denyCollection: sourceShapes equals: Bag empty.
+	sourceProjectController := sourceWorkbench projectController.
+	sourceProjectController saveProjectTo: file.
+
+	targetProject := OPProjectController fromFile: file.
+	targetWorkbench := targetProject open.
+	targetWorkbench showAllElementsInAllDiagrams.
+	targetEditor := targetWorkbench focusedEditor.
+	targetCanvas := targetEditor canvasPresenter canvas.
+	targetShapes := targetCanvas shapes
+		                collect: [ :each | each class ]
+		                as: Bag.
+	self assertCollection: targetShapes equals: sourceShapes
+]
diff --git a/repository/OpenPonk-Core/OPMementoDirectorySerializer.class.st b/repository/OpenPonk-Core/OPMementoDirectorySerializer.class.st
index 464acb34..f5ed31f4 100644
--- a/repository/OpenPonk-Core/OPMementoDirectorySerializer.class.st
+++ b/repository/OpenPonk-Core/OPMementoDirectorySerializer.class.st
@@ -121,6 +121,6 @@ OPMementoDirectorySerializer >> saveModelOf: aMemento to: aFolder [
 	modelSerializer class saveExportInfoTo: aFolder.
 	(aFolder / 'model' , modelSerializer formatName)
 		ensureDelete;
-		writeStreamDo: [ :stream | 
+		writeStreamDo: [ :stream |
 			stream nextPutAll: (modelSerializer serializeModel: aMemento model) ]
 ]
diff --git a/repository/OpenPonk-Core/OPModelObjectReference.class.st b/repository/OpenPonk-Core/OPModelObjectReference.class.st
index 1b8b6945..6974af0f 100644
--- a/repository/OpenPonk-Core/OPModelObjectReference.class.st
+++ b/repository/OpenPonk-Core/OPModelObjectReference.class.st
@@ -22,9 +22,9 @@ OPModelObjectReference >> = otherModelObject [
 ]
 
 { #category : 'comparing' }
-OPModelObjectReference >> modelObjectFrom: aDictionary [
+OPModelObjectReference >> modelObjectFrom: aCollection [
 
-	^ aDictionary at: uuid
+	^ aCollection detect: [ :any | any uuid = uuid ]
 ]
 
 { #category : 'printing' }
diff --git a/repository/OpenPonk-Core/OPProjectController.class.st b/repository/OpenPonk-Core/OPProjectController.class.st
index 9e1f193a..9825252b 100644
--- a/repository/OpenPonk-Core/OPProjectController.class.st
+++ b/repository/OpenPonk-Core/OPProjectController.class.st
@@ -24,16 +24,14 @@ Class {
 { #category : 'instance creation' }
 OPProjectController class >> fromDirectory: aFolder [
 
-	^ [ :job | 
-	  | materializer |
-	  job title: 'Reading project from file'.
-	  materializer := aFolder files
-		                  detect: [ :any | 
-		                  any basename = OPExportInfo fileName ]
-		                  ifFound: [ :exportInfoFile | 
-		                  OPSerializer forExportInfoFile: exportInfoFile ]
-		                  ifNone: [ OPProjectDirectoryMaterializer new ].
-	  materializer loadProjectFrom: aFolder asFileReference ] asJob run
+	| materializer |
+	materializer := aFolder files
+		                detect: [ :any |
+		                any basename = OPExportInfo fileName ]
+		                ifFound: [ :exportInfoFile |
+		                OPSerializer forExportInfoFile: exportInfoFile ]
+		                ifNone: [ OPProjectDirectoryMaterializer new ].
+	^ materializer loadProjectFrom: aFolder asFileReference
 ]
 
 { #category : 'opening' }
diff --git a/repository/OpenPonk-Core/OPShape.class.st b/repository/OpenPonk-Core/OPShape.class.st
index 0a1658d1..dab3b030 100644
--- a/repository/OpenPonk-Core/OPShape.class.st
+++ b/repository/OpenPonk-Core/OPShape.class.st
@@ -426,18 +426,18 @@ OPShape >> resizableInteractionTarget [
 ]
 
 { #category : 'serialization' }
-OPShape >> resolveAllModelElements: aDictionary [
+OPShape >> resolveAllModelElements: aCollection [
 
-	self resolveModelElements: aDictionary.
+	self resolveModelElements: aCollection.
 	self ownedElements do: [ :each | 
-		each resolveAllModelElements: aDictionary ]
+		each resolveAllModelElements: aCollection ]
 ]
 
 { #category : 'serialization' }
-OPShape >> resolveModelElements: aDictionary [
+OPShape >> resolveModelElements: aCollection [
 
-	self modelElements: (self modelElements collect: [ :each | 
-			 each modelObjectFrom: aDictionary ])
+	self modelElements: (self modelElements collect: [ :each |
+			 each modelObjectFrom: aCollection ])
 ]
 
 { #category : 'rendering' }
diff --git a/repository/OpenPonk-Core/OPStonDiagramSerializer.class.st b/repository/OpenPonk-Core/OPStonDiagramSerializer.class.st
index a3280861..9128e152 100644
--- a/repository/OpenPonk-Core/OPStonDiagramSerializer.class.st
+++ b/repository/OpenPonk-Core/OPStonDiagramSerializer.class.st
@@ -32,13 +32,11 @@ OPStonDiagramSerializer >> formatName [
 { #category : 'serialize/materialize' }
 OPStonDiagramSerializer >> materializeDiagramOf: aModel from: aStream [
 
-	| diagram adapters allModelElements |
+	| diagram innerElements |
 	diagram := STON fromStream: aStream.
-	adapters := OPNavigatorAdapters new.
-	allModelElements := ((Set with: aModel)
-	                     , (adapters allChildrenFor: aModel) collect: [ 
-		                     :each | each uuid -> each ]) asDictionary.
-	diagram resolveAllModelElements: allModelElements.
+	innerElements := OPNavigatorAdapters new allChildrenFor: aModel.
+	diagram resolveAllModelElements:
+		(innerElements asArray copyWith: aModel).
 	^ diagram
 ]
 
diff --git a/repository/OpenPonk-Spec/OPDefaultNavigatorAdapter.class.st b/repository/OpenPonk-Spec/OPDefaultNavigatorAdapter.class.st
index 809c74d4..d6c84891 100644
--- a/repository/OpenPonk-Spec/OPDefaultNavigatorAdapter.class.st
+++ b/repository/OpenPonk-Spec/OPDefaultNavigatorAdapter.class.st
@@ -39,13 +39,14 @@ OPDefaultNavigatorAdapter >> displayMapping [
 	OPProject -> 'Project'}
 ]
 
-{ #category : 'widget API' }
+{ #category : 'testing' }
 OPDefaultNavigatorAdapter >> hasMappingFor: anObject in: aModel [
 
 	^ {
 		  OPProject.
-		  OPTestContainerModel } anySatisfy: [ :any |
-		  anObject isKindOf: any ]
+		  OPTestContainerModel.
+		  OPTestEntityModel.
+		  OPTestRelationModel } anySatisfy: [ :any | anObject isKindOf: any ]
 ]
 
 { #category : 'widget API' }