diff --git a/src/libs/modelinglib/qmt/diagram_controller/diagramcontroller.h b/src/libs/modelinglib/qmt/diagram_controller/diagramcontroller.h
index e84cec69209..cf9d12f09c8 100644
--- a/src/libs/modelinglib/qmt/diagram_controller/diagramcontroller.h
+++ b/src/libs/modelinglib/qmt/diagram_controller/diagramcontroller.h
@@ -71,16 +71,16 @@ public:
 signals:
     void beginResetAllDiagrams();
     void endResetAllDiagrams();
-    void beginResetDiagram(const MDiagram *diagram);
-    void endResetDiagram(const MDiagram *diagram);
-    void beginUpdateElement(int row, const MDiagram *diagram);
-    void endUpdateElement(int row, const MDiagram *diagram);
-    void beginInsertElement(int row, const MDiagram *diagram);
-    void endInsertElement(int row, const MDiagram *diagram);
-    void beginRemoveElement(int row, const MDiagram *diagram);
-    void endRemoveElement(int row, const MDiagram *diagram);
-    void modified(const MDiagram *diagram);
-    void diagramAboutToBeRemoved(const MDiagram *diagram);
+    void beginResetDiagram(const qmt::MDiagram *diagram);
+    void endResetDiagram(const qmt::MDiagram *diagram);
+    void beginUpdateElement(int row, const qmt::MDiagram *diagram);
+    void endUpdateElement(int row, const qmt::MDiagram *diagram);
+    void beginInsertElement(int row, const qmt::MDiagram *diagram);
+    void endInsertElement(int row, const qmt::MDiagram *diagram);
+    void beginRemoveElement(int row, const qmt::MDiagram *diagram);
+    void endRemoveElement(int row, const qmt::MDiagram *diagram);
+    void modified(const qmt::MDiagram *diagram);
+    void diagramAboutToBeRemoved(const qmt::MDiagram *diagram);
 
 public:
     ModelController *modelController() const { return m_modelController; }
diff --git a/src/libs/modelinglib/qmt/diagram_scene/diagramscenemodel.h b/src/libs/modelinglib/qmt/diagram_scene/diagramscenemodel.h
index 3a669da5d0b..98ad9a7677a 100644
--- a/src/libs/modelinglib/qmt/diagram_scene/diagramscenemodel.h
+++ b/src/libs/modelinglib/qmt/diagram_scene/diagramscenemodel.h
@@ -80,8 +80,8 @@ public:
     ~DiagramSceneModel() override;
 
 signals:
-    void diagramSceneActivated(const MDiagram *diagram);
-    void selectionHasChanged(const MDiagram *diagram);
+    void diagramSceneActivated(const qmt::MDiagram *diagram);
+    void selectionHasChanged(const qmt::MDiagram *diagram);
     void sceneRectChanged(const QRectF &sceneRect);
 
 public:
diff --git a/src/libs/modelinglib/qmt/diagram_ui/diagramsmanager.h b/src/libs/modelinglib/qmt/diagram_ui/diagramsmanager.h
index 226c2389a54..cb5298d7237 100644
--- a/src/libs/modelinglib/qmt/diagram_ui/diagramsmanager.h
+++ b/src/libs/modelinglib/qmt/diagram_ui/diagramsmanager.h
@@ -61,8 +61,8 @@ public:
 
 signals:
     void someDiagramOpened(bool);
-    void diagramActivated(const MDiagram *diagram);
-    void diagramSelectionChanged(const MDiagram *diagram);
+    void diagramActivated(const qmt::MDiagram *diagram);
+    void diagramSelectionChanged(const qmt::MDiagram *diagram);
 
 public:
     void setModel(TreeModel *model);
diff --git a/src/libs/modelinglib/qmt/diagram_widgets_ui/diagramsview.h b/src/libs/modelinglib/qmt/diagram_widgets_ui/diagramsview.h
index ec8cc026a4c..7e1fa7df3b8 100644
--- a/src/libs/modelinglib/qmt/diagram_widgets_ui/diagramsview.h
+++ b/src/libs/modelinglib/qmt/diagram_widgets_ui/diagramsview.h
@@ -50,8 +50,8 @@ public:
     ~DiagramsView() override;
 
 signals:
-    void currentDiagramChanged(const MDiagram *diagram);
-    void diagramCloseRequested(const MDiagram *diagram);
+    void currentDiagramChanged(const qmt::MDiagram *diagram);
+    void diagramCloseRequested(const qmt::MDiagram *diagram);
     void someDiagramOpened(bool);
 
 public:
diff --git a/src/libs/modelinglib/qmt/diagram_widgets_ui/stackeddiagramsview.h b/src/libs/modelinglib/qmt/diagram_widgets_ui/stackeddiagramsview.h
index 36822ea245e..2f045e6da67 100644
--- a/src/libs/modelinglib/qmt/diagram_widgets_ui/stackeddiagramsview.h
+++ b/src/libs/modelinglib/qmt/diagram_widgets_ui/stackeddiagramsview.h
@@ -49,8 +49,8 @@ public:
     ~StackedDiagramsView() override;
 
 signals:
-    void currentDiagramChanged(const MDiagram *diagram);
-    void diagramCloseRequested(const MDiagram *diagram);
+    void currentDiagramChanged(const qmt::MDiagram *diagram);
+    void diagramCloseRequested(const qmt::MDiagram *diagram);
     void someDiagramOpened(bool);
 
 public:
diff --git a/src/libs/modelinglib/qmt/tasks/diagramscenecontroller.h b/src/libs/modelinglib/qmt/tasks/diagramscenecontroller.h
index 5f925df48b5..c13d3aab26c 100644
--- a/src/libs/modelinglib/qmt/tasks/diagramscenecontroller.h
+++ b/src/libs/modelinglib/qmt/tasks/diagramscenecontroller.h
@@ -72,8 +72,8 @@ public:
     ~DiagramSceneController() override;
 
 signals:
-    void newElementCreated(DElement *element, MDiagram *diagram);
-    void elementAdded(DElement *element, MDiagram *diagram);
+    void newElementCreated(DElement *element, qmt::MDiagram *diagram);
+    void elementAdded(DElement *element, qmt::MDiagram *diagram);
 
 public:
     ModelController *modelController() const { return m_modelController; }
diff --git a/src/plugins/modeleditor/modeleditor_plugin.cpp b/src/plugins/modeleditor/modeleditor_plugin.cpp
index 67756e94642..17f5c26ae87 100644
--- a/src/plugins/modeleditor/modeleditor_plugin.cpp
+++ b/src/plugins/modeleditor/modeleditor_plugin.cpp
@@ -34,7 +34,8 @@
 #include "uicontroller.h"
 #include "actionhandler.h"
 
-#include "qmt/infrastructure/uid.h"
+#include <qmt/infrastructure/uid.h>
+#include <qmt/model/mdiagram.h>
 
 #include <coreplugin/actionmanager/actioncontainer.h>
 #include <coreplugin/actionmanager/actionmanager.h>
@@ -70,6 +71,8 @@ ModelEditorPlugin::ModelEditorPlugin()
     pluginInstance = this;
     qRegisterMetaType<QItemSelection>("QItemSelection");
     qRegisterMetaType<qmt::Uid>("qmt::Uid");
+    qRegisterMetaType<qmt::MDiagram *>();
+    qRegisterMetaType<const qmt::MDiagram *>();
 }
 
 ModelEditorPlugin::~ModelEditorPlugin()