Cell[TextData[{"Basic Examples", "  ", Cell["(4)", "ExampleCount"]}],
   "ExampleSection", "ExampleSection"]

CounterBoxOptions->{CounterFunction:>CapitalRomanNumeral}]

SetOptions[
 EvaluationNotebook[],
 NotebookEventActions -> {
   {"MenuCommand", "Save"} :> (Scan[
      Module[{nr},
        SelectionMove[#, All, CellGroup, AutoScroll -> False];
        nr = Length @ Select[
           SelectedCells[],
           Experimental`CellStyleNames[#] === "Input" & (*1*)
        ];
        SetOptions[#, CellDingbat -> "(" <> ToString[nr] <> ")"];
      ] &
      ,
      Cells[CellStyle -> "Section"] (*2*)
   ]),
   PassEventsDown -> True
   }
 ]

SetOptions[EvaluationNotebook[],
     NotebookEventActions -> {{"MenuCommand",
         "Save"} :> (Scan[
          Module[{nr},
            SelectionMove[#, All, CellGroup, AutoScroll -> False];

            nr = Length@
              Select[SelectedCells[],
               Experimental`CellStyleNames[#] ===
                 "ItemNumbered" & (*1*)];

            SetOptions[#,
             CellDingbat ->
              Cell[BoxData[
                PaneBox[
                 StyleBox[ToString[nr] <> "   ",
                  RGBColor[0.5, 0.5, 0.67, 0.81],
                  FontFamily -> "Continuum Light", 15],
                 Alignment -> Right, ImageSize -> 40]],
               Background -> White]];] &,
          Cells[CellStyle -> "Subsection"] (*2*)]),
       PassEventsDown -> True}]

SetOptions[
    EvaluationNotebook[],
    StyleDefinitions -> Notebook[
        {
        Cell[StyleData[StyleDefinitions -> "Default.nb"]],
        Cell[StyleData["Input"],
            CounterIncrements -> "CellCount"
        ],
        Cell[StyleData["Notebook"],
            TaggingRules -> "TotalCells" -> Dynamic[Length[Cells[CellStyle -> "Input"]]]
        ],
        Cell[StyleData["Section"],
            CellDingbat -> Cell @ BoxData @ DynamicBox[
                RowBox[{
                    "(",
                    ToBoxes[
                        AbsoluteCurrentValue[ParentCell[EvaluationCell[]], {TaggingRules, "NextSection"}] -
                        AbsoluteCurrentValue[ParentCell[EvaluationCell[]], {TaggingRules, "ThisSection"}]
                    ],
                    ")"
                }]
            ],
            TaggingRules -> {
                "NextSection" -> Dynamic @ Replace[
                    NextCell[CellStyle -> "Section"],
                    {
                    None :> CurrentValue[EvaluationNotebook[], {TaggingRules, "TotalCells"}],
                    o_ :> CurrentValue[o, {"CounterValue", "CellCount"}]
                    }
                ],
                "ThisSection" -> Dynamic[CurrentValue[EvaluationCell[], {"CounterValue", "CellCount"}]]}],
        },
        StyleDefinitions -> "PrivateStylesheetFormatting.nb"
    ]
]