diff --git a/Polyhedron/demo/Polyhedron/MainWindow.cpp b/Polyhedron/demo/Polyhedron/MainWindow.cpp
index 17ec86d1207..9db867b1a6e 100644
--- a/Polyhedron/demo/Polyhedron/MainWindow.cpp
+++ b/Polyhedron/demo/Polyhedron/MainWindow.cpp
@@ -1493,6 +1493,7 @@ void MainWindow::showSceneContextMenu(int selectedItemIndex,
     }
   }
   menu->addMenu(ui->menuOperations);
+
   if(menu)
     menu->exec(global_pos);
 }
@@ -1755,6 +1756,7 @@ void MainWindow::showSceneContextMenu(const QPoint& p) {
         QAction* saveas = menu.addAction(tr("&Save as..."));
         connect(saveas,  SIGNAL(triggered()),
                 this, SLOT(on_actionSaveAs_triggered()));
+        menu.addMenu(ui->menuOperations);
         menu.exec(sender->mapToGlobal(p));
         return;
       }
@@ -2189,7 +2191,7 @@ void MainWindow::on_actionShowHide_triggered()
     item->redraw();
   }
   scene->setUpdatesEnabled(true);
-  updateViewersBboxes(false);
+//  updateViewersBboxes(false); //Not usable :when the scene changes scale, smaller items disappear.
 }
 
 void MainWindow::on_actionSetPolyhedronA_triggered()
diff --git a/Polyhedron/demo/Polyhedron/Plugins/PCA/Basic_generator_plugin.cpp b/Polyhedron/demo/Polyhedron/Plugins/PCA/Basic_generator_plugin.cpp
index 269eb121ae4..4d92aeb7867 100644
--- a/Polyhedron/demo/Polyhedron/Plugins/PCA/Basic_generator_plugin.cpp
+++ b/Polyhedron/demo/Polyhedron/Plugins/PCA/Basic_generator_plugin.cpp
@@ -766,7 +766,7 @@ struct Point_generator
   {
     return Point(bl.x() + i*(ur.x()-bl.x())/(w-1),
                  bl.y() + j*(ur.y()-bl.y())/(h-1),
-                 0);
+                 bl.z() + j*(ur.z()-bl.z())/(h-1));
   }
 };
 template<class Facegraph_item>
diff --git a/Polyhedron/demo/Polyhedron/Plugins/PMP/Orient_soup_plugin.cpp b/Polyhedron/demo/Polyhedron/Plugins/PMP/Orient_soup_plugin.cpp
index 265507b8a9c..6d2d062e002 100644
--- a/Polyhedron/demo/Polyhedron/Plugins/PMP/Orient_soup_plugin.cpp
+++ b/Polyhedron/demo/Polyhedron/Plugins/PMP/Orient_soup_plugin.cpp
@@ -223,8 +223,8 @@ void Polyhedron_demo_orient_soup_plugin::apply_shuffle( Item* root_item,
   item->load(root_item);
   item->shuffle_orientations();
   item->setColor(root_item->color());
-  scene->replaceItem(index, item);
-  delete root_item;
+  scene->replaceItem(index, item, true);
+  root_item->deleteLater();
   QApplication::restoreOverrideCursor();
 }
 
diff --git a/Polyhedron/demo/Polyhedron/Scene.cpp b/Polyhedron/demo/Polyhedron/Scene.cpp
index 5425285d9ed..4730d595adb 100644
--- a/Polyhedron/demo/Polyhedron/Scene.cpp
+++ b/Polyhedron/demo/Polyhedron/Scene.cpp
@@ -143,6 +143,7 @@ Scene::replaceItem(Scene::Item_id index, CGAL::Three::Scene_item* item, bool emi
 
     if(emit_item_about_to_be_destroyed) {
       Q_EMIT itemAboutToBeDestroyed(item);
+      item->aboutToBeDestroyed();
     }
 
     Q_EMIT updated();
diff --git a/Polyhedron/demo/Polyhedron/Scene_c3t3_item.cpp b/Polyhedron/demo/Polyhedron/Scene_c3t3_item.cpp
index 9ad4cfa9dc2..2c383d3b8ed 100644
--- a/Polyhedron/demo/Polyhedron/Scene_c3t3_item.cpp
+++ b/Polyhedron/demo/Polyhedron/Scene_c3t3_item.cpp
@@ -1453,6 +1453,7 @@ void Scene_c3t3_item_priv::computeElements()
    }
   
   positions_poly.clear();
+  positions_grid.clear();
   normals.clear();
   f_colors.clear();
   positions_lines.clear();