procedure TForm1.mSaveImageClick(Sender: TObject);
var
  SaveImageEnDialog1: ieopensavedlg.TSaveImageEnDialog;
begin
  // Create the dialog at runtime
  SaveImageEnDialog1 := TSaveImageEnDialog.Create(nil);
  try
    // Todo: display all image formats in the TSaveImageEnDialog with iesfImagesOnly, defaulting to PNG:
    SaveImageEnDialog1.ShowFormats := iesfImagesOnly; // this does work
    //SaveImageEnDialog1.DefaultExt := 'png';         // this does not work

    // Attach the dialog to the ImageEnView's IO component:
    SaveImageEnDialog1.AttachedImageEnIO := ImageEnView1.IO;

    // Execute the dialog
    if SaveImageEnDialog1.Execute() then
      ImageEnView1.IO.SaveToFile(SaveImageEnDialog1.Filename);
  finally
    // Free the dialog to prevent memory leaks
    SaveImageEnDialog1.Free;
  end;
end;