The default Look&Feel (skin) can be changed by editing the marvin.properties file (in the user's home/chemaxon directory) and inserting/changing the "skin=..." line to the following:

• Metal Look&Feel
  skin=javax.swing.plaf.metal.MetalLookAndFeel

• Nimbus Look&Feel
  skin=com.sun.java.swing.plaf.nimbus.NimbusLookAndFeel

• CDE/Motif Look&Feel
  skin=com.sun.java.swing.plaf.motif.MotifLookAndFeel

• Windows Look&Feel
  (Default on Windows, can be deleted) skin=com.sun.java.swing.plaf.windows.WindowsLookAndFeel

• Windows Classic Look&Feel
  skin=com.sun.java.swing.plaf.windows.WindowsClassicLookAndFeel

• Jgoodies Plastic XP Look&Feel
  skin=com.jgoodies.looks.plastic.PlasticXPLookAndFeel

• Jgoodies Plastic Look&Feel
  skin=com.jgoodies.looks.plastic.PlasticLookAndFeel