Picturebox and other questions

[multigamedk]

Okay this is my code:

    Private Sub Form1_MouseDown(ByVal sender As Object, ByVal e As System.Windows.Forms.MouseEventArgs) Handles Me.MouseDown
        Dim pb As New PictureBox
        pb.Location = e.Location
        pb.ImageLocation = TextBox1.Text
        Me.Controls.Add(pb)
        pb.Height = 32
        pb.Width = 32

    End Sub

It does that you click on something in the form then it will create a Picturebox.
Okay what I want more is this:

1. It should only can be made one picture box every 32x32 like this:

If you dont know what I mean then just forgot it but please try.

2. When I right click on the mouse the Picturebox should be deleted.

Thanks for helping!