WpViewPdf Memory leak

begin
      wp:=TWPViewPDF.CreateParented(application.handle);
      wp.plus.Enable(0);
      wp.LoadFromFile(strpas(fileName)) ;
      if true then
      begin
          StampMeta:=TmetaFile.create;
          StampMetaCan := TMetafileCanvas.Create(StampMeta,0);
          try


         StampMetaCan.Font.Height := dati.font_height;
         StampMetaCan.Font.Color := dati.text_color;
         StampMetaCan.Font.Name := dati.font_name;
         StampMetaCan.Font.size:=dati.font_size;
         StampMetaCan.Brush.Style := bsClear;


         aForm.eM11 := 1;
         aForm.eM12 := 0;
         aForm.eM21 := 0;
         aForm.eM22 := 1;


         aForm.eDx := Screen.PixelsPerInch;
         aForm.eDy := Screen.PixelsPerInch*2;
         SetWorldTransform(StampMetaCan.Handle, aForm);






          y:=WPCentimeterToPixel(dati.posY_cm,72);
          x:=WPCentimeterToPixel(dati.posx_cm,72);


                lst:=TStringlist.create;
                lst.text:=strpas(dati.testo);
                idx:=0;
                for n := lst.count - 1 downto 0 do
                begin
                   StampMetaCan.TextOut(x,y-(15*(n+1)), lst[idx]);
                   inc(idx);
                end;
                lst.free;


         nrP:=wp.CommandEx(COMPDF_GetPageCount,0);




          finally
               StampMetaCan.Free;
          end;
          wp.CommandStrEx(495,inttostr(nrP)+'-'+inttostr(nrP), StampMeta.Handle)
          wp.Plus.SetSecurityMode(wpNoSecurity);
          wp.Plus.SaveToFile(pchar(szNomeFile));


          StampMeta.free;


      end;
      wp.clear;
      wp.free;
end;