has the vb.net syntax changed?

[oompa_l]

hi

some really simple vb stuff that was working before,is now not
working...and I have no idea why

here's the code:

  Sub RunScript(ByVal path As String)

    If (Not IO.File.Exists(path)) Then Return False

    Dim lines As String() = IO.File.ReadAllLines(path)
    If (lines Is Nothing) Then Return False

    Dim pts As New List(Of On3dPoint)
    Dim labels As New List(Of String)
    Dim radii As New List(Of Double)

    'Dim temperature As New List(Of Color
    'Dim humidity As New List(Of String)

    For Each line As String In lines
      Dim parts As String() = line.Split(",".ToCharArray())

      Dim x As Double = Convert.ToDouble(parts(0))
      Dim y As Double = Convert.ToDouble(parts(1))
      Dim z As Double = Convert.ToDouble(parts(2))
      Dim radius As String = Convert.ToString(parts(3))
      Dim label As String = Convert.ToString(parts(5))

      pts.Add(New On3dPoint(x, y, z))
      radii.Add(radius)
      labels.Add(label)
    Next

    A = pts
    B = labels
    C = radii
  End Sub

I am getting error message about "Return statement in a 'sub' or 'set'
cannot return a value."

Also, is it possible to go back to an earlier version of grasshopper?
Are the old ones still available? Can we have multiple versions
installed at the same time?

thanks!