When the program starts, it sets its Timer to 2 seconds. When the timer fires the first time, it resets its interval to 25 milliseconds. Each time the Timer event fires, the program moves the form a bit more to the right until it reaches its original position. At that point, the splash screen unloads itself.

Private Form1Left As Single

Private Sub Form_Load()
    ' Displays image to size of form regardless of
    ' screen resolution
    Image1.Move 0, 0, ScaleWidth, ScaleHeight
    Me.Show

    ' Start wiping in 2 seconds.
    Timer1.Interval = 2000
End Sub

Private Sub Timer1_Timer()
Static done_before As Boolean

Dim new_left As Single

    ' See if this is the first time.
    If Not done_before Then
        ' It's the first time. Start wiping the
        ' main form over the splash screen.
        done_before = True
        Timer1.Interval = 25
        Form1Left = Form1.Left
        Form1.Left = -Form1.Width
        Form1.Visible = True
    End If

    new_left = Form1.Left + 240
    If new_left > Form1Left Then
        new_left = Form1Left
        Unload Me
    End If

    Form1.Left = new_left
End Sub