Hi,
Sorry, I test on my side. Unfortunately, I am not able to reproduce. Items still don’t show CheckMargin and ImageMargn.
Could you please provide more details or make a demo project for us to test? Please upload your demo project to some server and offer us the URL. Skydrive (http://skydrive.live.com/ ) may be a good option. You can sign up 25GB free space only with your Windows Live Passport.
I use the following code;
private void button1_Click(object sender, EventArgs e)
{
ContextMenuStrip cms = new ContextMenuStrip();
cms.ShowCheckMargin = false;
cms.ShowImageMargin = false;
cms.AutoSize = false;
TextBox textbox1 = new TextBox();
textbox1.Text = "11111111111111111111";
//ExtraControl esc = new ExtraControl();
cms.Items.Add(new ToolStripControlHost(textbox1));
cms.ClientSize = new Size(500,500);
cms.Padding = new Padding(0);
cms.Margin = new Padding(0);
cms.Items.Add("aaaaaaaaaaaaa", Image.FromFile(@"C:\Users\##\Desktop\test.jpg"));
cms.Show(this.Location);
}

Best regards,
Ling Wang
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