Private Declare Function GetWindowLong Lib "user32" Alias "GetWindowLongA" (ByVal hwnd As Long, ByVal nIndex 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 Declare Function SetLayeredWindowAttributes Lib "user32.dll" (ByVal hwnd As Long, ByVal crKey As Long, ByVal bAlpha As Byte, ByVal dwFlags As Long) As Long
Private Declare Function SendMessage Lib "user32" Alias "SendMessageA" (ByVal hwnd As Long, ByVal wMsg As Long, ByVal wParam As Long, lParam As Any) As Long
Private Declare Function ReleaseCapture Lib "user32" () As Long
 
Private Sub Form_Load()
    'Llamamos a la función, enviamos el nombre del Form y el Color de fondo
    MakeSkin Form1, vbWhite
End Sub
 
Private Sub MakeSkin(ByVal Frm As Form, ByVal BColor As Long)
    'Función que "recorta" un formulario según su color de fondo.
    Frm.BackColor = BColor
    Tmp = GetWindowLong(Frm.hwnd, -20)
    Tmp = Tmp Or &H80000
    SetWindowLong Frm.hwnd, -20, &H80000
    SetLayeredWindowAttributes Frm.hwnd, BColor, 0, &H1
End Sub
 
Private Sub Form_MouseDown(Button As Integer, Shift As Integer, X As Single, Y As Single)
    'Permite mover el formulario al hacer click encima de él
    ReleaseCapture
    SendMessage Me.hwnd, &HA1, 2, 0&
End Sub