// Add a layer file as a merged image (as a single layer) to the current content
ImageEnView1.LayersImport( 'C:\Layers.ien', nil, ioIEN, True );

// Add all layers of a layer file (as separate layers) to the current content
ImageEnView1.IO.LoadFromFileIEN( 'C:\Layers.ien', True );

// Toggle auto-shrink when pressing the Ctrl key
procedure TForm1.ImageEnView1KeyDown(Sender: TObject; var Key: Word; Shift: TShiftState);
begin
  if Key = VK_CONTROL then
  begin
    ImageEnView1.AutoShrink := not ImageEnView1.AutoShrink;
    if not ImageEnView1.AutoShrink then
      ImageEnView1.Fit()
    else
      ImageEnView1.Zoom := 100;
  end;
end;