for i := 0 to _prop_Bitmaps.Count-1 do 
          begin
              ImgLst.ImgWidth := 16;
              ImgLst.ImgHeight := 16;
              ImgLst.AddMasked(_prop_Bitmaps.Objects[i], clWhite)
          end;

        ImgLst.ImgWidth := 16;
        ImgLst.ImgHeight := 16;
        for i := 0 to _prop_Bitmaps.Count-1 do 
         ImgLst.AddMasked(_prop_Bitmaps.Objects[i], clWhite)