// Calling EXE code:
// Delayed and Dynamic loading have the same result
  procedure ImageEn; external 'TwainScannerDebugging.dll' name 'ImageEN' delayed;
.
.
.
procedure TForm1.Button1Click(Sender: TObject);
begin
  ImageEn;
end;

// DLL code:
procedure ImageEN;
var
  Frm: TFrmImageViewer;
begin
  Frm := TFrmImageViewer.Create(nil);
  try
    Frm.ShowModal;
  finally
    FreeAndNil(Frm);
  end;
end;

// TFrmImageViewer
procedure TFrmImageViewer.Button1Click(Sender: TObject);
begin
  ImgEnMIOView.MIO.Acquire;
end;

procedure TFrmImageViewer.Button2Click(Sender: TObject);
begin
  ImgEnMIOView.MIO.SelectAcquireSource();
  Label2.Caption := ImgEnMIOView.MIO.SelectedAcquireSource.Name;

  Button1.Enabled := True;
end;

// DFM
    object ImgEnMIOView: TImageEnMView
      Left = 1
      Top = 1
      Width = 216
      Height = 598
      Background = clBtnFace
      Ctl3D = False
      ParentCtl3D = False
      StoreType = ietNormal
      ThumbWidth = 100
      ThumbHeight = 100
      HorizBorder = 4
      VertBorder = 4
      GridWidth = 0
      SelectionColor = 13542013
      Style = iemsACD
      ThumbnailsBackground = clBtnFace
      ThumbnailsBackgroundSelected = clBtnFace
      MultiSelectionOptions = []
      ThumbnailsBorderWidth = 0
      DefaultBottomText = iedtNone
      Align = alLeft
      ThumbnailResampleFilter = rfFastLinear
      ThumbnailDisplayFilter = rfNone
      SelectedFontColor = clNone
      MouseWheelParams.Action = iemwVScroll
      MouseWheelParamsAlt.Action = iemwZoom
      TabOrder = 0
    end
    object ImgEnView: TImageEnView
      Left = 217
      Top = 1
      Width = 796
      Height = 598
      Background = clBtnFace
      Ctl3D = False
      ParentCtl3D = False
      LegacyBitmap = True
      EnableInteractionHints = True
      MouseWheelParams.Action = iemwZoom
      Align = alClient
      TabOrder = 1
    end