IGxDialog hangs when on sub forms

Hi, I have been tackling this error for days. I am in Arg10.0 Windows 7 using Engine. This all worked in 9.3, but now converting I have having some issues with accessing files. The following code works fine in the main form(I use 0 for the parentWindow), but it doesn't work on any sub forms. I have tried adding the IntPtr value, but same error "VSHOST.EXE has stopped working". it just hands trying to navigate to folders.

Dim pGxDialog As IGxDialog
Dim pSel As IEnumGxObject = Nothing
Dim pGxobj As IGxObject = Nothing

Dim Result(2) As String

Try

pGxDialog = New GxDialog
pGxDialog.AllowMultiSelect = False
pGxDialog.StartingLocation = "C:\"
pGxDialog.Title = Title_Display
pGxDialog.ObjectFilter = New GxFilterShapefiles


Dim vptr As IntPtr
vptr = Me.Handle


'make sure something was selected
If Not pGxDialog.DoModalOpen(pvtr.ToInt32, pSel) Then
Exit Function
End If


thanks