GridViewComboBoxColumn not selecting previously saved value

[spam]

I have a grid w/ a combobox in the first column. If I exclude SelectedValueMemberPath="ID", the default value doesn't get chosen when I load up the grid BUT the comboBOx is populated. If I include SelectedValueMemberPath="ID" in the xaml, the same thing happens except after a i select a value in the column, if i click on another column, the value in the combobox dissappears & the combobox is blanked. Forcing me to reselect. 

Can someone please provide an answer to this problem or an example project that has a telerik 
grid w/ a comobox that allows me to save the combox value and reopen the grid w/ the saved value selected? 

I've been working on this 5 days now. :(

Thank you kindly.

PS: I should also mention, the values in the combobox come from 2 tables & combines. One of them doesn't have IDs so I generate unique interger IDs in C# when the value data is loaded. The value generated are consistent each time & not random.

<telerikGridView:RadGridView Name="grdSortSequence" IsReadOnly="False"
                                        VerticalAlignment="Stretch"
                                        ItemsSource="{Binding SortSequenceLines, Mode=TwoWay}"
                                        SelectedItem="{Binding SelectedSequenceLine, Mode=TwoWay}"
                                        AutoGenerateColumns="False"
                                        IsFilteringAllowed="False"
                                        RowIndicatorVisibility="Collapsed"
                                        ShowGroupPanel="False"
                                        CanUserDeleteRows="True"
                                        Margin="2"
                                        MinHeight="150" MaxHeight="200"
                                        Grid.Column="0" Grid.ColumnSpan="2" Grid.Row="6" Width="400" Height="160">
            <telerikGridView:RadGridView.Columns>

                <telerikGridView:GridViewComboBoxColumn Header="ChangeAttributeTo" UniqueName="AttributeName" Width="120"  ValidatesOnDataErrors="None"
                                                    DataMemberBinding="{Binding Attribute, Mode=TwoWay}"
                                                    DisplayMemberPath="Name"
                                                    SelectedValueMemberPath="ID"/>

                <telerikGridView:GridViewDataColumn x:Name="txtAttribute"
                                                    Header="Attribute"
                                                    Background="Silver"
                                                    IsReadOnly="True"
                                                    DataMemberBinding="{Binding AttributeName, Mode=TwoWay}"
                                                    UniqueName="AttributeName" />

                <telerikGridView:GridViewDataColumn x:Name="txtLength"
                                                    Header="Length"
                                                    DataMemberBinding="{Binding Length, Mode=TwoWay}"
                                                    UniqueName="Length" />

                <telerikGridView:GridViewDataColumn x:Name="chkIsDescending"
                                                    Header="Descending"
                                                    DataMemberBinding="{Binding IsDescending, Mode=TwoWay}"
                                                    UniqueName="Descending" />

                <telerikGridView:GridViewDataColumn x:Name="txtSequence"
                                                    Header="Sequence"
                                                    DataMemberBinding="{Binding SequenceNumber, Mode=TwoWay}"
                                                    UniqueName="Name" />

            </telerikGridView:RadGridView.Columns>
        </telerikGridView:RadGridView>

This is my class that reflex a record in the grid...

public class SequenceLine
{
    public GeneralSettings.Module.ViewModels.Attribute Attribute { get; set; }
    public string AttributeName { get; set; }
    public int ClassCodeGroupID { get; set; }
    public int SequenceNumber { get; set; }
    public int Length { get; set; }
    public Boolean? IsDescending { get; set; }
}

And this is the Attribute class that is in the comboBox.

 

public class Attribute
{
    public int ID { get; set; }
    public string Name { get; set; }
}

[spam]

Can Anyone help me on this? NO comments at all? Really?