check.Sh.Width = 500 + 500 * Rnd

Option Explicit
Dim colShapes() As ShaperType
Private Type ShaperType
   Sh As Shape
   StepX As Integer
   StepY As Integer
End Type

Private Sub Form_Load()
Show
  ReDim colShapes(0)
  addshape
  Timer1.Enabled = True
End Sub

Private Sub Timer1_Timer()
 Dim i As Integer
  For i = 1 To UBound(colShapes)
    If One_step(colShapes(i)) Then
       addshape
    End If
  Next i
End Sub

Private Function One_step(ByRef mama As ShaperType) As Boolean
With mama.Sh
    .Left = .Left + mama.StepX
    .Top = .Top + mama.StepY
    If .Left >= Form1.Width - .Width Then
       One_step = True
       mama.StepX = -200 * Rnd
    Else
       One_step = False
    End If
    If .Left <= 0 Then
       mama.StepX = 200 * Rnd
    End If
    If .Top >= Form1.Height - .Width Then mama.StepY = -300 * Rnd
    If .Top <= 0 Then mama.StepY = 300 * Rnd
End With
End Function

Private Sub addshape()
Dim check As ShaperType
  Set check.Sh = Me.Controls.Add("VB.Shape", "sh" & UBound(colShapes) + 1)
  check.Sh.Visible = 1
  check.Sh.Shape = 3
  'check.Sh.FillStyle = vbSolid
  'check.Sh.FillColor = 16777216 * Rnd
  'check.Sh.Width = 500 + 500 * Rnd
  check.StepX = 200 * Rnd
  check.StepY = 300 * Rnd
  ReDim Preserve colShapes(UBound(colShapes) + 1)
  colShapes(UBound(colShapes)) = check
End Sub

check.Sh.Width = 500 + 500 * Rnd

check.Sh.Width = 200 + 500 * Rnd