diff --git a/repository/OpenPonk-BormEditor/BormNodeShape.class.st b/repository/OpenPonk-BormEditor/BormNodeShape.class.st
index 374655e..21cbef1 100644
--- a/repository/OpenPonk-BormEditor/BormNodeShape.class.st
+++ b/repository/OpenPonk-BormEditor/BormNodeShape.class.st
@@ -36,6 +36,14 @@ BormNodeShape >> plusIconAction: aBlock [
 	plusIconAction := aBlock
 ]
 
+{ #category : 'removing' }
+BormNodeShape >> removeRender [
+
+	super removeRender.
+	plusIcon := nil.
+	labeled := nil
+]
+
 { #category : 'rendering' }
 BormNodeShape >> renderShapeDetails [
 
diff --git a/repository/OpenPonk-BormEditor/BormParticipantShape.class.st b/repository/OpenPonk-BormEditor/BormParticipantShape.class.st
index 6e038d6..de91bdf 100644
--- a/repository/OpenPonk-BormEditor/BormParticipantShape.class.st
+++ b/repository/OpenPonk-BormEditor/BormParticipantShape.class.st
@@ -43,6 +43,13 @@ BormParticipantShape >> innerRoassalShapesBlock: aBlock [
 	innerRoassalShapesBlock := aBlock
 ]
 
+{ #category : 'removing' }
+BormParticipantShape >> removeRender [
+
+	super removeRender.
+	icon := nil
+]
+
 { #category : 'rendering' }
 BormParticipantShape >> renderBasicShape [
 
diff --git a/repository/OpenPonk-BormEditor/BormStateShape.class.st b/repository/OpenPonk-BormEditor/BormStateShape.class.st
index 3f78461..fb3c9d0 100644
--- a/repository/OpenPonk-BormEditor/BormStateShape.class.st
+++ b/repository/OpenPonk-BormEditor/BormStateShape.class.st
@@ -10,6 +10,14 @@ Class {
 	#tag : 'Shapes'
 }
 
+{ #category : 'removing' }
+BormStateShape >> removeRender [
+
+	super removeRender.
+	playIcon := nil.
+	innerBox := nil
+]
+
 { #category : 'rendering' }
 BormStateShape >> renderBasicShape [
 
diff --git a/repository/OpenPonk-BormEditor/OPBormAssociationEnhancementController.class.st b/repository/OpenPonk-BormEditor/OPBormAssociationEnhancementController.class.st
index e8ad043..f257d49 100644
--- a/repository/OpenPonk-BormEditor/OPBormAssociationEnhancementController.class.st
+++ b/repository/OpenPonk-BormEditor/OPBormAssociationEnhancementController.class.st
@@ -15,8 +15,7 @@ OPBormAssociationEnhancementController >> dependingOnElements [
 ]
 
 { #category : 'diagram elements' }
-OPBormAssociationEnhancementController >> diagramElementOwner [
+OPBormAssociationEnhancementController >> owner [
 
-	^ (self diagramController controllerForModel: model owner)
-		  diagramElement
+	^ self diagramController controllerForModel: model owner
 ]
diff --git a/repository/OpenPonk-BormEditor/OPBormParticipantController.class.st b/repository/OpenPonk-BormEditor/OPBormParticipantController.class.st
index ee8f2c0..2012589 100644
--- a/repository/OpenPonk-BormEditor/OPBormParticipantController.class.st
+++ b/repository/OpenPonk-BormEditor/OPBormParticipantController.class.st
@@ -67,3 +67,11 @@ OPBormParticipantController >> removeModel [
 	self model owner remove: self model.
 	super removeModel
 ]
+
+{ #category : 'diagram elements' }
+OPBormParticipantController >> unhookDiagramElement [
+
+	super unhookDiagramElement.
+	(self diagramElement ifNotExists: [ ^ self ])
+		innerRoassalShapesBlock: [  ]
+]
diff --git a/repository/OpenPonk-BormEditor/OPBormProcessNodeController.class.st b/repository/OpenPonk-BormEditor/OPBormProcessNodeController.class.st
index d25cfde..af0967a 100644
--- a/repository/OpenPonk-BormEditor/OPBormProcessNodeController.class.st
+++ b/repository/OpenPonk-BormEditor/OPBormProcessNodeController.class.st
@@ -69,3 +69,11 @@ OPBormProcessNodeController >> removeModel [
 	self model owner remove: self model.
 	super removeModel
 ]
+
+{ #category : 'diagram elements' }
+OPBormProcessNodeController >> unhookDiagramElement [
+
+	super unhookDiagramElement.
+
+	(self diagramElement ifNotExists: [ ^ self ]) plusIconAction: [  ]
+]