This works in VS2013 net FrameWork4.5
Put declare and constant at top of class
Usage put rest of code in Form_Load as in example code.
Private Declare Function SendMessageByNum Lib "user32" Alias "SendMessageA" _
(ByVal hwnd As IntPtr, ByVal wMsg As UInt32, ByVal wParam As IntPtr, ByVal lParam As IntPtr) As IntPtr
Private Const lB_SETITEMHEIGHT As Integer = &H1A0
Private Sub Form_Load(ByVal sender As Object, ByVal e As System.EventArgs) Handles Me.Load
Dim ItemHeight As Integer = Me.Font.Height + 4
SendMessageByNum(CheckedListBoxControl.Handle, lB_SETITEMHEIGHT, CType(0, IntPtr), CType(ItemHeight, IntPtr))
End Sub