Turns out it was easy,
Code:
Sub Freeze_Panes() 'button click macro to freeze panes at row 4 and col A or Col H
If ActiveWindow.SplitRow = 3 And ActiveWindow.SplitColumn = 7 Then
ActiveWindow.SplitRow = 3
ActiveWindow.SplitColumn = 0
ActiveWindow.FreezePanes = True
ActiveSheet.Shapes("FP").TextFrame.Characters.Text = "Freeze" & vbCrLf & "Pane"
Else
ActiveWindow.SplitRow = 3
ActiveWindow.SplitColumn = 7
ActiveWindow.FreezePanes = True
ActiveSheet.Shapes("FP").TextFrame.Characters.Text = "Un-Freze" & vbCrLf & "Pane"
End If
End Sub