Private Declare Function GetWindowLong Lib "user32" Alias "GetWindowLongA" ( _
  ByVal hWnd As Long, ByVal nIndex As Long) As Long
 
Private Declare Function SetLayeredWindowAttributes Lib "user32" (ByVal hWnd As _
  Long, _
  ByVal crKey As Long, ByVal bAlpha As Byte, ByVal dwFlags As Long) As Long
 
Private Declare Function SetWindowLong Lib "user32" Alias "SetWindowLongA" ( _
  ByVal hWnd As Long, ByVal nIndex As Long, ByVal dwNewLong As Long) As Long
 
Private Const GWL_EXSTYLE& = -20
Private Const LWA_COLORKEY& = &H1
Private Const WS_EX_LAYERED& = &H80000
'
 
Private Sub Form_Load()
 
  Me.BackColor = vbCyan
  Call SetWindowLong(Me.hWnd, GWL_EXSTYLE, GetWindowLong(Me.hWnd, GWL_EXSTYLE) _
    Or WS_EX_LAYERED)
  Call SetLayeredWindowAttributes(Me.hWnd, Me.BackColor, 0, LWA_COLORKEY)
 
End Sub

Gruss,

Zardoz