* Fixed keyboard shortcuts.

* Reverted crash on node deletion fix as it's fixed in the latest GraphView.

MaterialGraphProject/Assets/GraphFramework/SerializableGraph/Editor/Drawing/Drawer/NodeDrawer.cs

             m_CurrentControlPresenter = new List<GraphControlPresenter>();
 
             usePixelCaching = false;
+
+            // Nodes need to be focusable to make the keyboard shortcuts work.
+            focusIndex = 0;
         }
 
         private void AddControls(GraphNodePresenter nodeData)

MaterialGraphProject/Assets/GraphFramework/SerializableGraph/Editor/Drawing/SerializableGraphView.cs

             Insert(0, new GridBackground());
 
             typeFactory[typeof(GraphNodePresenter)] = typeof(NodeDrawer);
+
+            // Make this GraphView focusable or keyboard shortcuts won't work.
+            focusIndex = 0;
         }
 
         // TODO JOCE Remove the "new" here. Use the base class' impl
 
             ClearSelection();
             foreach (var drawer in selectedDrawers)
-            {
-                if (drawer != null)
-                    AddToSelection(drawer);
-            }
+                AddToSelection(drawer);
         }
 
         public void SetGlobalSelection()