swixml框架例子有问题，求救

import com.toedter.calendar.*;
import org.swixml.SwingEngine;
import org.swixml.ConverterLibrary;
import org.jvnet.substance.SubstanceLookAndFeel;
import org.jvnet.substance.theme.SubstanceEbonyTheme;import javax.swing.*;
import java.awt.event.WindowAdapter;
import java.awt.event.WindowEvent;public class CustomTags extends WindowAdapter {
  public CustomTags() throws Exception {
    SwingEngine swix = new SwingEngine(this);
    swix.getTaglib().registerTag("Calendar", JCalendar.class);
    swix.render("customtags.xml").setVisible(true);
  }  /**
   * Invoked when a window is in the process of being closed.
   * The close operation can be overridden at this point.
   */
  public void windowClosing(WindowEvent e) {
    super.windowClosing(e);
    System.exit(0);
  }  //
  //  Make the class bootable
  //
  public static void main(String[] args) throws Exception {
    new CustomTags();
  }
}这是xml
<?xml version="1.0" encoding="UTF-8" ?>
<frame title="Swixml: Custom Tags" size="400,260" defaultCloseOperation="JFrame.EXIT_ON_CLOSE">
       <!--plaf="org.jvnet.substance.skin.SubstanceRavenLookAndFeel">                              -->
  <panel layout="BorderLayout">
    <panel  border="TitledBorder(JCalendar,0,1,VERDANA-BOLD-18)"   background="white" constraints="BorderLayout.NORTH">
      <label font="Comic Sans MS-BOLD-18" foreground="black">Custom Components in Swixml</label>
    </panel>
    <calendar initclass="java.util.Date"/>
  </panel>
</frame>生成的效果没有例子中的图片那么漂亮