it requires some coding, but this should give you the result you're looking for:

Public Class Form1
    Private _currentDataPointSymbol As Symbol
    Private Property CurrentDataPointSymbol() As Symbol
        Get
            Return Me._currentDataPointSymbol
        End Get
        Set(ByVal value As Symbol)
            Me._currentDataPointSymbol = value
        End Set
    End Property
    Private _currentLabel As String
    Private Property CurrentLabel() As String
        Get
            Return Me._currentLabel
        End Get
        Set(ByVal value As String)
            Me._currentLabel = value
        End Set
    End Property
    Private Sub UltraChart1_ChartDataClicked(ByVal sender As Object, ByVal e As ChartDataEventArgs) Handles UltraChart1.ChartDataClicked
        If TypeOf e.Primitive Is DataPoint Then
            Dim dP As DataPoint = CType(e.Primitive, DataPoint)
            Me.CurrentDataPointSymbol = New Symbol(dP.point, SymbolIcon.Circle, SymbolIconSize.Large)
            Me.CurrentDataPointSymbol.PE = New PaintElement(Color.Red)
            Me.CurrentLabel = dP.DataPoint.Label
            Me.UltraChart1.InvalidateLayers()
        End If
    End Sub

    Private Sub UltraChart1_FillSceneGraph(ByVal sender As System.Object, ByVal e As FillSceneGraphEventArgs) Handles UltraChart1.FillSceneGraph
        For Each p As Primitive In e.SceneGraph
            If TypeOf p Is Text Then
                Dim t As Text = CType(p, Text)
                If t.GetTextString() = Me.CurrentLabel Then
                    t.labelStyle.FontColor = Color.Red
                End If
            End If
        Next
        If Not Me.CurrentDataPointSymbol Is Nothing Then
            e.SceneGraph.Add(Me.CurrentDataPointSymbol)
        End If
    End Sub
End Class