I am trying to load a URLControl based on data from a database.  I have most of it figured out.  However, when I try to set the 'Open Link In New Window' checkbox as being checked using the below code, no error occurs, but the checkbox never gets checked.  Any help would be appreciated.

                                CheckBox chkNewWindow = (CheckBox)UrlControl.FindControl("chkNewWindow");
                                chkNewWindow.Checked = true;

 
I know this is an old thread but I just ran into the same issue and came up with this simple solution that works.

DotNetNuke.UI.UserControls.UrlControl dnnUrl = (DotNetNuke.UI.UserControls.UrlControl)edit.FindControl("ctlURL");
dnnUrl.ShowNewWindow = true;
dnnUrl.ShowLog = false;
dnnUrl.ShowTrack = false;
 
dnnUrl.PreRender += new EventHandler(dnnUrl_PreRender);

        void dnnUrl_PreRender(object sender, EventArgs e)
        {
            DotNetNuke.UI.UserControls.UrlControl dnnUrl = (DotNetNuke.UI.UserControls.UrlControl)sender;
            CheckBox chkNewWindow = (CheckBox)dnnUrl.FindControl("chkNewWindow");
            chkNewWindow.Checked = true;
        }