VBA - Change Task Cell Background Color based on cell value

The routine below loops through all rows in the Project and, based on the number in one custom field, changes the background color of that cell.  Works fine, except:

The problem is that this routine loops through tasks and then uses "SelectTaskField Row:= taskID" to get to the field/cell that I want to modify.  To make this work I have to do "OutlineShowAllTasks", so that the Row number will correlate with the Task ID.  That changes the display of tasks that are closed.

(The routine toggles the "Change Highlighting" because otherwise that will override the highlighting that the routine makes).

Solutions might be:

1) address the field by task instead of row

2) recognize which tasks are closed, memorize those, then re-open them

3) something else?

Any suggestions on this would be appreciated 

Sub SetPriorityColors()

Dim wrkCHFlag As Boolean
wrkCHFlag = False

If EnableChangeHighlighting Then
ToggleChangeHighlighting
wrkCHFlag = True
End If

    ScreenUpdating = False
    ScreenUpdating = True

Set ts = ActiveProject.Tasks
For n = 1 To ts.Count
    If Not ts(n) Is Nothing Then
        ts(n).OutlineShowAllTasks
    End If
Next n

For n = 1 To ts.Count
    If Not ts(n) Is Nothing Then
        Set tsk = ts(n)

        SelectTaskField Row:=tsk.ID, Column:="Number10", RowRelative:=False

        Select Case tsk.Number10
            Case Is >= 9
                Font32Ex CellColor:=&HFF99CC
            Case Is >= 8
                Font32Ex CellColor:=&H66CCFF
            Case Is >= 7
                Font32Ex CellColor:=&H66FFFF
             Case Is = 0
                 Font32Ex CellColor:=&HFFFFFF
             Case Is = 3
                 Font32Ex CellColor:=&HFFCC99
        End Select

   End If

Next n

If wrkCHFlag Then
    ToggleChangeHighlighting
 End If

SelectTaskField Row:="1", Column:="Number10", RowRelative:=False
End Sub