"don't update" links & calculating cells

I have a workbook (A) that has links to and will open 3 other workbooks
(B,C,D)when opened. One of these 3 workbooks (B) has links to the other two
(C,D). I have the following startup macro.

Private Sub Workbook_Open()
Application.DisplayAlerts = False
Workbooks.Open Filename:= "C.xls", UpdateLinks:=False
Workbooks.Open Filename:= "D.xls", UpdateLinks:=False
Workbooks.Open Filename:= "B.xls", UpdateLinks:=False
Windows("A.xls").Activate
Application.DisplayAlerts = True
End Sub

Woorkbooks C & D open in about 5 seconds. The problem is that workbook B
takes about 60 seconds to open because it goes through "calculating cells".
Is there anyway to not have it go through its update? I have tried modifying
the registry by placing a DWORD - FullCalcOnLoadOldFile = 0 on the
Excel/Options section. That didnt work.