[SOLVED] Checkbox visibility setting fails

[SOLVED] Problem in the creation, resulting in duplicates of checkboxes stacking on top of each other
New code:

Public Sub addcheckboxes(ByVal Lower As String, ByVal Upper As String)
Dim ws As Worksheet, myObjectname As String, addChk As Boolean

Set ws = Workbooks("nursery.xls").Worksheets("Seeding")
Application.ScreenUpdating = False

ckbox = Lower
' add a checkbox for printing
For Each cell In ws.Range("g" & Lower & ":g" & Upper)

myObjectname = "ckboxPrintLabels" & ckbox
addChk = True

For Each ctrl In ActiveSheet.CheckBoxes
' nasty hack to overcome the limitations of vba in excel - no eval!
If ctrl.name = myObjectname Then
addChk = False ' if chkbox already exists
ctrl.Visible = True 'switch to visible, as it may not be
End If
Next

If addChk Then
With ws.CheckBoxes.Add(cell.Left, _
cell.Top, cell.Width, cell.Height)
.LinkedCell = cell
.Interior.ColorIndex = xlNone
.Caption = ""
.name = myObjectname
.Visible = True
End With
End If
ckbox = ckbox + 1
Next
Application.ScreenUpdating = True
End Sub