Add the ability to access the ColumnChooser opening in order to set its properties. Currently, every time when the user opens the ColumnChoser new instance is created and because of this its properties and events are no longer available. This feature will 

Resolution:
Add the ColumnChooserCreated event which access and  allow to customize the ColumnChooser. 

//subscribe to the event ColumnChooserCreated
this.radGridView1.ColumnChooserCreated += new ColumnChooserCreatedEventHandler(radGridView1_ColumnChooserCreated);
			
//customize the ColumnChooser
void radGridView1_ColumnChooserCreated(object sender, Telerik.WinControls.UI.ColumnChooserCreatedEventArgs e)
{
    e.ColumnChooser.ForeColor = Color.DarkGreen;
    e.ColumnChooser.Text = "My title";
    e.ColumnChooser.ColumnChooserControl.ColumnChooserElement.Font = this.Font;
    e.ColumnChooser.ColumnChooserControl.ColumnChooserElement.Text = "My text";
}