private void SaveAs(TmNode node)
 {
     saveFileDialog1.FileName = node.Name;
     if (saveFileDialog1.ShowDialog(this) == DialogResult.OK)
     {
         try
         {
             if (node.IsThemeList)
                 node.SaveAs(saveFileDialog1.FileName);
             else if (node.IsCategory)
             {
                 themesTreeView.Add(node.CopyAsThemeList(saveFileDialog1.FileName));
             }
             else
                 MessageBox.Show("Save As... is only valid on a Theme List or a Category");
         }
         catch (Exception ex)
         {
             MessageBox.Show(string.Format("Unable to save Theme List '{0}'\n in file '{1}'\n{2}", node.Name, saveFileDialog1.FileName, ex.Message),
                             "Oh no!");
         }
     }
 }