To reproduce: the attached gif file illustrates the behavior.

public Form2()
{
    InitializeComponent();

    this.radGridView1.DataSource = this.customersBindingSource;
    this.radGridView1.CellClick += radGridView1_CellClick;
}

private void radGridView1_CellClick(object sender, Telerik.WinControls.UI.GridViewCellEventArgs e)
{
    this.radDataLayout1.DataSource = e.Row.DataBoundItem;
    this.radDataEntry1.DataSource = e.Row.DataBoundItem;
}

private void Form2_Load(object sender, EventArgs e)
{
    // TODO: This line of code loads data into the 'nwindDataSet1.Customers' table. You can move, or remove it, as needed.
    this.customersTableAdapter.Fill(this.nwindDataSet1.Customers);
}