Using Marlett for optional selections - multiple ranges

[bwait]

Hi,
I am using Marlett checkboxes to implement three mutually-exclusive checkboxes (columns A, B, and C). I found some Worksheet code that makes these mutually exclusive (for example, checking A1, clears A1:C1, then sets A1 to Marlett "a"). But, I want the checkboxes on a row to be optional as well as mutually-exclusive. For example, a user can check box A or B or C, or none of them. The code I have wont allow this. Any ideas how to implement this?

Thanks
Brad

Here is the code I am using:

Private Sub Worksheet_SelectionChange(ByVal Target As Range)
    If Target.Cells.Count > 1 Then Exit Sub
    If Target.Column >= 1 And Target.Column <= 4 Then
        If Not Intersect(Target, Range("A" & Target.Row & ":C" & Target.Row)) Is Nothing Then
            Target.Font.Name = "Marlett"
            Range("A" & Target.Row & ":C" & Target.Row).ClearContents
            If Target = vbNullString Then
                Target = "a"
            Else
                Target = vbNullString
            End If
        End If
    End If
End Sub

[bwait]

FYI, I did a workaround, where I inserted a new column A that serves as a "clear all" checkbox for that row. The remaining three checkbox columns (now B, C, and D) remain mutually exclusive, but not optional.
A user can clear their checkboxes on a row by clicking in the A cell. For example, click A3 clears B33.
Here is the code:

Private Sub Worksheet_SelectionChange(ByVal Target As Range)    If Target.Cells.Count > 1 Then Exit Sub
    If Target.Column >= 1 And Target.Column <= 5 Then
        'Enable mutually-exclusive selection of cells B, C, or D.
        'That is, clear B:D and then reset target-selected cell to be
        'a Marlett 'a', which displays as a checkmark.
        If Not Intersect(Target, Range("B" & Target.Row & ":D" & Target.Row)) Is Nothing Then
            Target.Font.Name = "Marlett"
            Range("B" & Target.Row & ":D" & Target.Row).ClearContents
            If Target = vbNullString Then
                Target = "a"
            Else
                Target = vbNullString
            End If
            Else
            'Enable clicking cell in column A to clear columns B:D
            'Column A is Marlett 'r', which displays as an X, but not until it
            'is clicked the first time.
                If Not Intersect(Target, Range("A" & Target.Row)) Is Nothing Then
                Target.Font.Name = "Marlett"
                Target = "r"
                Range("B" & Target.Row & ":D" & Target.Row).ClearContents
            End If
        End If
    End If
End Sub

[大灰狼1976]

Hi bwait!
The following code is a little simpler.

Private Sub Worksheet_SelectionChange(ByVal Target As Range)
    If Target.Count > 1 Then Exit Sub
    If Target.Column > 4 Then Exit Sub
    Dim s$
    If Target.Column = 1 Then s = "r" Else s = "a"
    Cells(Target.Row, 2).Resize(, 3).ClearContents
    Target.Font.Name = "Marlett"
    Target = s
End Sub