CreateRegn

Private Declare Function CreateEllipticRgn Lib "gdi32" _
(ByVal X1 As Long, ByVal Y1 As Long, ByVal X2 As Long, _
ByVal Y2 As Long) As Long
Private Declare Function SetWindowRgn Lib "user32" _
(ByVal hWnd As Long, ByVal hRgn As Long, ByVal bRedraw _
As Boolean) As Long
Private Sub Form_Load()
Show 'IL form!
SetWindowRgn hWnd, _
CreateEllipticRgn(0, 0, 300, 200), True
End Sub