diff --git a/src/main/java/de/neemann/digital/gui/Main.java b/src/main/java/de/neemann/digital/gui/Main.java
index 3df268a80..e1396820a 100644
--- a/src/main/java/de/neemann/digital/gui/Main.java
+++ b/src/main/java/de/neemann/digital/gui/Main.java
@@ -39,7 +39,7 @@ public class Main extends JFrame implements ClosingWindowListener.ConfirmSave {
     private static final String MESSAGE = "Digital\n\nA simple simulator for digital circuits.\nWritten bei H.Neemann in 2016";
     private final CircuitComponent circuitComponent;
     private final ToolTipAction save;
-    private final PartLibrary library = ShapeFactory.INSTANCE.setLibrary(new PartLibrary());
+    private final PartLibrary library = ShapeFactory.getInstance().setLibrary(new PartLibrary());
     private final ToolTipAction doStep;
     private File filename;
     private Model model;
@@ -71,17 +71,21 @@ public class Main extends JFrame implements ClosingWindowListener.ConfirmSave {
         ToolTipAction newFile = new ToolTipAction("New") {
             @Override
             public void actionPerformed(ActionEvent e) {
-                setFilename(null);
-                circuitComponent.setCircuit(new Circuit());
+                if (ClosingWindowListener.checkForSave(Main.this, Main.this)) {
+                    setFilename(null);
+                    circuitComponent.setCircuit(new Circuit());
+                }
             }
         };
 
         ToolTipAction open = new ToolTipAction("Open") {
             @Override
             public void actionPerformed(ActionEvent e) {
-                JFileChooser fc = getjFileChooser();
-                if (fc.showOpenDialog(Main.this) == JFileChooser.APPROVE_OPTION) {
-                    loadFile(fc.getSelectedFile());
+                if (ClosingWindowListener.checkForSave(Main.this, Main.this)) {
+                    JFileChooser fc = getjFileChooser();
+                    if (fc.showOpenDialog(Main.this) == JFileChooser.APPROVE_OPTION) {
+                        loadFile(fc.getSelectedFile());
+                    }
                 }
             }
         };
diff --git a/src/main/java/de/neemann/digital/gui/draw/graphics/Style.java b/src/main/java/de/neemann/digital/gui/draw/graphics/Style.java
index 14ac537d0..930cb0eb2 100644
--- a/src/main/java/de/neemann/digital/gui/draw/graphics/Style.java
+++ b/src/main/java/de/neemann/digital/gui/draw/graphics/Style.java
@@ -7,6 +7,7 @@ import java.awt.*;
  */
 public class Style {
     public static final Style NORMAL = new Style(2, false, Color.BLACK);
+    public static final Style WIRE = new Style(2, true, Color.BLUE.darker());
     public static final Style WIRE_LOW = new Style(3, true, new Color(0, 112, 0));
     public static final Style WIRE_HIGH = new Style(3, true, new Color(102, 255, 102));
     public static final Style FILLED = new Style(2, true, Color.BLACK);
diff --git a/src/main/java/de/neemann/digital/gui/draw/parts/VisualPart.java b/src/main/java/de/neemann/digital/gui/draw/parts/VisualPart.java
index 575d4e5ef..db46f5af3 100644
--- a/src/main/java/de/neemann/digital/gui/draw/parts/VisualPart.java
+++ b/src/main/java/de/neemann/digital/gui/draw/parts/VisualPart.java
@@ -26,7 +26,7 @@ public class VisualPart implements Drawable, Moveable, AttributeListener {
     private transient Shape shape;
     private transient IOState ioState;
     private transient Interactor interactor;
-    private transient boolean highLight = true;
+    private transient boolean highLight = false;
     private Vector pos;
     private int rotate;
 
@@ -83,7 +83,7 @@ public class VisualPart implements Drawable, Moveable, AttributeListener {
 
     public Shape getShape() {
         if (shape == null)
-            shape = ShapeFactory.INSTANCE.getShape(partName, partAttributes);
+            shape = ShapeFactory.getInstance().getShape(partName, partAttributes);
         return shape;
     }
 
diff --git a/src/main/java/de/neemann/digital/gui/draw/parts/Wire.java b/src/main/java/de/neemann/digital/gui/draw/parts/Wire.java
index edeb08ede..e15c87238 100644
--- a/src/main/java/de/neemann/digital/gui/draw/parts/Wire.java
+++ b/src/main/java/de/neemann/digital/gui/draw/parts/Wire.java
@@ -25,7 +25,7 @@ public class Wire implements Drawable, Moveable {
 
     @Override
     public void drawTo(Graphic graphic) {
-        Style style = Style.FILLED;
+        Style style = Style.WIRE;
 
         Vector r = RAD;
         if (value != null) {
diff --git a/src/main/java/de/neemann/digital/gui/draw/shapes/ShapeFactory.java b/src/main/java/de/neemann/digital/gui/draw/shapes/ShapeFactory.java
index 2bf79a856..0d13c0eac 100644
--- a/src/main/java/de/neemann/digital/gui/draw/shapes/ShapeFactory.java
+++ b/src/main/java/de/neemann/digital/gui/draw/shapes/ShapeFactory.java
@@ -20,7 +20,7 @@ import java.util.HashMap;
  * @author hneemann
  */
 public final class ShapeFactory {
-    public static final ShapeFactory INSTANCE = new ShapeFactory();
+
     public HashMap<String, Creator> map = new HashMap<>();
     private PartLibrary library;
 
@@ -47,6 +47,10 @@ public final class ShapeFactory {
         map.put(Out.PROBEDESCRIPTION.getName(), attr -> new ProbeShape(attr.get(AttributeKey.Label)));
     }
 
+    public static ShapeFactory getInstance() {
+        return InstanceHolder.INSTANCE;
+    }
+
     public PartLibrary setLibrary(PartLibrary library) {
         this.library = library;
         return library;
@@ -85,6 +89,10 @@ public final class ShapeFactory {
         Shape create(PartAttributes attributes);
     }
 
+    private static final class InstanceHolder {
+        static final ShapeFactory INSTANCE = new ShapeFactory();
+    }
+
     public class CreatorSimple implements Creator {
 
         private final String name;