Private Sub imgSplitter_MouseDown(Button As Integer, Shift As Integer, X As Single, Y As Single)
  With imgSplitter
    picSplitter.Move .left, .top, .Width \  2 , .Height -  20 
  End With
  
  picSplitter.Visible = True
  Globals.mbMoving = True
End Sub

Private Sub imgSplitter_MouseMove(Button As Integer, Shift As Integer, X As Single, Y As Single)
    If Globals.mbMoving Then
        picSplitter.left = X + imgSplitter.left
    End If
End Sub

Private Sub imgSplitter_MouseUp(Button As Integer, Shift As Integer, X As Single, Y As Single)
  SizeControls picSplitter.left 'Это фу-я, где все имеющееся на форме передвигается в соответствии с новым положением сплиттера
  picSplitter.Visible = False
  Globals.mbMoving = False
End Sub