diff --git a/src/gui/MainWindow.cpp b/src/gui/MainWindow.cpp
index 10c58cd..c944745 100644
--- a/src/gui/MainWindow.cpp
+++ b/src/gui/MainWindow.cpp
@@ -2689,6 +2689,9 @@ void MainWindow::addPaintItem(uid paintId, const QIcon& icon, const QString& nam
 
   // Set size.
   item->setSizeHint(QSize(item->sizeHint().width(), MainWindow::PAINT_LIST_ITEM_HEIGHT));
+  
+  // Set tooltip.
+  item->setToolTip(QString("ID: %1").arg(paint->getId()));
 
   // Switch to paint tab.
   contentTab->setCurrentWidget(paintSplitter);
@@ -2721,7 +2724,7 @@ void MainWindow::addMappingItem(uid mappingId)
   Mapping::ptr mapping = mappingManager->getMappingById(mappingId);
   Q_CHECK_PTR(mapping);
 
-  QString label;
+  QString defaultName;
   QIcon icon;
 
   QString shapeType = mapping->getShape()->getType();
@@ -2743,7 +2746,7 @@ void MainWindow::addMappingItem(uid mappingId)
   // Triangle
   if (shapeType == "triangle")
   {
-    label = QString("Triangle %1").arg(mappingId);
+    defaultName = QString("Triangle %1").arg(mappingId);
     icon = QIcon(":/shape-triangle");
 
     if (paintType == "color")
@@ -2754,7 +2757,7 @@ void MainWindow::addMappingItem(uid mappingId)
   // Mesh
   else if (shapeType == "mesh")
   {
-    label = QString("Mesh %1").arg(mappingId);
+    defaultName = QString("Mesh %1").arg(mappingId);
     icon = QIcon(":/shape-mesh");
     if (paintType == "color")
       mapper = MappingGui::ptr(new MeshColorMappingGui(mapping));
@@ -2763,7 +2766,7 @@ void MainWindow::addMappingItem(uid mappingId)
   }
   else if (shapeType == "ellipse")
   {
-    label = QString("Ellipse %1").arg(mappingId);
+    defaultName = QString("Ellipse %1").arg(mappingId);
     icon = QIcon(":/shape-ellipse");
     if (paintType == "color")
       mapper = MappingGui::ptr(new EllipseColorMappingGui(mapping));
@@ -2772,13 +2775,13 @@ void MainWindow::addMappingItem(uid mappingId)
   }
   else
   {
-    label = QString("Polygon %1").arg(mappingId);
+    defaultName = QString("Polygon %1").arg(mappingId);
     icon = QIcon(":/shape-polygon");
   }
 
   // Label is only going to be applied if no name is present.
-  if (!mapping->getName().isEmpty())
-    label = mapping->getName();
+  if (mapping->getName().isEmpty())
+    mapping->setName(defaultName);
 
   // Add to list of mappers.
   mappers[mappingId] = mapper;
@@ -2808,7 +2811,7 @@ void MainWindow::addMappingItem(uid mappingId)
   contentTab->setCurrentWidget(mappingSplitter);
 
   // Add item to layerList widget.
-  mappingListModel->addItem(mapping, icon, label);
+  mappingListModel->addItem(mapping, icon, mapping->getName());
   mappingListModel->updateModel();
   setCurrentMapping(mappingId);
 
diff --git a/src/gui/MappingGui.cpp b/src/gui/MappingGui.cpp
index 536ee73..4aef3e8 100644
--- a/src/gui/MappingGui.cpp
+++ b/src/gui/MappingGui.cpp
@@ -35,12 +35,13 @@ MappingGui::MappingGui(Mapping::ptr mapping)
   _variantManager = new VariantManager;
   _variantFactory = new VariantFactory;
 
-  _topItem = _variantManager->addProperty(QtVariantPropertyManager::groupTypeId(),
-                                          QObject::tr("Mapping"));
-
   _propertyBrowser->setFactoryForManager(_variantManager, _variantFactory);
-
-  _propertyBrowser->addProperty(_topItem);
+  
+  // Mapping UID.
+  _idItem = _variantManager->addProperty(QVariant::Int, QObject::tr("ID"));
+  _idItem->setEnabled(false);
+  _idItem->setValue(_mapping->getId());
+  _propertyBrowser->addProperty(_idItem);
 
   // Mapping basic properties.
   _opacityItem = _variantManager->addProperty(QVariant::Double, QObject::tr("Opacity (%)"));
@@ -48,14 +49,14 @@ MappingGui::MappingGui(Mapping::ptr mapping)
   _opacityItem->setAttribute("maximum", 100.0);
   _opacityItem->setAttribute("decimals", 1);
   _opacityItem->setValue(_mapping->getOpacity()*100.0);
-  _topItem->addSubProperty(_opacityItem);
+  _propertyBrowser->addProperty(_opacityItem);
 
   // Output shape.
   _outputItem = _variantManager->addProperty(QtVariantPropertyManager::groupTypeId(),
                                              QObject::tr("Output shape"));
 
   _buildShapeProperty(_outputItem, mapping->getShape().data());
-  _topItem->addSubProperty(_outputItem);
+  _propertyBrowser->addProperty(_outputItem);
 
   // Collapse output shape.
   _propertyBrowser->setExpanded(_propertyBrowser->items(_outputItem).at(0), false);
@@ -161,7 +162,7 @@ MeshColorMappingGui::MeshColorMappingGui(Mapping::ptr mapping)
   _meshItem = _variantManager->addProperty(QVariant::Size, QObject::tr("Dimensions"));
   _meshItem->setValue(QSize(mesh->nColumns(), mesh->nRows()));
   _meshItem->setAttribute("minimum", QSize(2,2));
-  _topItem->insertSubProperty(_meshItem, _opacityItem); // insert at the beginning
+  _propertyBrowser->insertProperty(_meshItem, _opacityItem); // insert at the beginning
 }
 
 void MeshColorMappingGui::setValue(QtProperty* property, const QVariant& value)
@@ -257,7 +258,7 @@ TextureMappingGui::TextureMappingGui(QSharedPointer<TextureMapping> mapping)
   _inputItem = _variantManager->addProperty(QtVariantPropertyManager::groupTypeId(),
                                             QObject::tr("Input shape"));
   _buildShapeProperty(_inputItem, inputShape.data());
-  _topItem->insertSubProperty(_inputItem, _opacityItem); // insert
+  _propertyBrowser->insertProperty(_inputItem, _opacityItem); // insert
 
   // Collapse input shape.
   _propertyBrowser->setExpanded(_propertyBrowser->items(_inputItem).at(0), false);
@@ -393,7 +394,7 @@ MeshTextureMappingGui::MeshTextureMappingGui(QSharedPointer<TextureMapping> mapp
   _meshItem = _variantManager->addProperty(QVariant::Size, QObject::tr("Dimensions"));
   _meshItem->setValue(QSize(mesh->nColumns(), mesh->nRows()));
   _meshItem->setAttribute("minimum", QSize(2,2));
-  _topItem->insertSubProperty(_meshItem, _opacityItem); // insert at the beginning
+  _propertyBrowser->insertProperty(_meshItem, _opacityItem); // insert at the beginning
 }
 
 void MeshTextureMappingGui::setValue(QtProperty* property, const QVariant& value)
diff --git a/src/gui/MappingGui.h b/src/gui/MappingGui.h
index 6bc93cb..aeffb34 100644
--- a/src/gui/MappingGui.h
+++ b/src/gui/MappingGui.h
@@ -98,7 +98,7 @@ protected:
   QtVariantEditorFactory* _variantFactory;
   QtVariantPropertyManager* _variantManager;
 
-  QtProperty* _topItem;
+  QtVariantProperty* _idItem;
   QtVariantProperty* _opacityItem;
   QtProperty* _outputItem;
 
diff --git a/src/gui/MappingListModel.cpp b/src/gui/MappingListModel.cpp
index f5763a6..c9bda41 100644
--- a/src/gui/MappingListModel.cpp
+++ b/src/gui/MappingListModel.cpp
@@ -47,9 +47,9 @@ QVariant MappingListModel::data(const QModelIndex &index, int role) const
   case Qt::SizeHintRole:
     if (index.column() == MM::HideColumn)
       return QSize(24, 40);
-    if (index.column() == MM::IconAndNameColum)
-      return QSize(135, 40);
-    if (index.column() == MM::GroupButtonColum)
+//    if (index.column() == MM::IconAndNameColum)
+//      return QSize(135, 40);
+    else if (index.column() == MM::GroupButtonColum)
       return QSize(128, 40);
     break;
   case Qt::CheckStateRole + 1:
@@ -70,6 +70,9 @@ QVariant MappingListModel::data(const QModelIndex &index, int role) const
   case Qt::DecorationRole:
     return mappingList.at(index.row()).icon;
     break;
+  case Qt::ToolTipRole:
+    return QString("ID: %1").arg(mappingList.at(index.row()).id);
+    break;
   default:
     return QVariant();
     break;
diff --git a/src/gui/PaintGui.cpp b/src/gui/PaintGui.cpp
index 7dc3c64..7cec736 100644
--- a/src/gui/PaintGui.cpp
+++ b/src/gui/PaintGui.cpp
@@ -29,15 +29,16 @@ PaintGui::PaintGui(Paint::ptr paint)
   _variantManager = new VariantManager;
   _variantFactory = new VariantFactory;
 
-  _topItem = _variantManager->addProperty(QtVariantPropertyManager::groupTypeId(),
-                                          QObject::tr("Paint"));
-
   _propertyBrowser->setFactoryForManager(_variantManager, _variantFactory);
 
   connect(_variantManager, SIGNAL(valueChanged(QtProperty*, const QVariant&)),
           this,            SLOT(setValue(QtProperty*, const QVariant&)));
 
-  _propertyBrowser->addProperty(_topItem);
+  // Mapping UID.
+  _idItem = _variantManager->addProperty(QVariant::Int, QObject::tr("ID"));
+  _idItem->setEnabled(false);
+  _idItem->setValue(_paint->getId());
+  _propertyBrowser->addProperty(_idItem);
 
   // Paint basic properties.
   _opacityItem = _variantManager->addProperty(QVariant::Double, QObject::tr("Opacity (%)"));
@@ -45,7 +46,7 @@ PaintGui::PaintGui(Paint::ptr paint)
   _opacityItem->setAttribute("maximum", 100.0);
   _opacityItem->setAttribute("decimals", 1);
   _opacityItem->setValue(_paint->getOpacity()*100.0);
-  _topItem->addSubProperty(_opacityItem);
+  _propertyBrowser->addProperty(_opacityItem);
 }
 
 PaintGui::~PaintGui()
@@ -88,7 +89,7 @@ ColorGui::ColorGui(Paint::ptr paint)
 
   _colorItem->setValue(color->getColor());
 
-  _topItem->addSubProperty(_colorItem);
+  _propertyBrowser->addProperty(_colorItem);
 }
 
 void ColorGui::setValue(QtProperty* property, const QVariant& value) {
@@ -130,8 +131,8 @@ _imageFileItem->setValue(image->getUri());
   _imageRateItem->setAttribute("decimals", 1);
   _imageRateItem->setValue(rate);
 
-  _topItem->addSubProperty(_imageFileItem);
-  _topItem->addSubProperty(_imageRateItem);
+  _propertyBrowser->addProperty(_imageFileItem);
+  _propertyBrowser->addProperty(_imageRateItem);
 }
 
 void ImageGui::setValue(QtProperty* property, const QVariant& value) {
@@ -190,10 +191,10 @@ VideoGui::VideoGui(Paint::ptr paint)
 //                                                tr("Reverse"));
 //  _mediaReverseItem->setValue(false);
 
-  _topItem->addSubProperty(_mediaFileItem);
-  _topItem->addSubProperty(_mediaRateItem);
-  _topItem->addSubProperty(_mediaVolumeItem);
-//  _topItem->addSubProperty(_mediaReverseItem);
+  _propertyBrowser->addProperty(_mediaFileItem);
+  _propertyBrowser->addProperty(_mediaRateItem);
+  _propertyBrowser->addProperty(_mediaVolumeItem);
+//  _propertyBrowser->addProperty(_mediaReverseItem);
 }
 
 void VideoGui::setValue(QtProperty* property, const QVariant& value)
diff --git a/src/gui/PaintGui.h b/src/gui/PaintGui.h
index 2aafceb..afbd8df 100644
--- a/src/gui/PaintGui.h
+++ b/src/gui/PaintGui.h
@@ -78,7 +78,8 @@ protected:
   QtAbstractPropertyBrowser* _propertyBrowser;
   QtVariantEditorFactory* _variantFactory;
   QtVariantPropertyManager* _variantManager;
-  QtProperty* _topItem;
+
+  QtVariantProperty* _idItem;
   QtVariantProperty* _opacityItem;
 };