Thank you for the attached sample, I have sucessfully replicated the issue on our end. I have submitted a bug report for this issue. We will inform you if there is any update / fix for this issue.

By default the grid style item will use EllipsisText, this way long text will automatically be truncated and you will need to mouse over the text to show the full text. Unfortunately, EllipsisText does not support text wrapping so you will need to modify the UXStackButton StackMenuStyle template to use TextBlock control that support text wrapping, hide the EllipsisText and create the a TextBloxk with similar style. Here is the modified section for the StackMenuStyle to use TextBlock in Grid item:

<Style x:Key="GridStyle" TargetType="Intersoft:UXStackItem">
	<Setter Property="Background" Value="Transparent"/>
	<Setter Property="BorderThickness" Value="1"/>
	<Setter Property="CornerRadius" Value="4"/>
	<Setter Property="IsTabStop" Value="False"/>
	<Setter Property="Padding" Value="4"/>
	<Setter Property="HorizontalAlignment" Value="Stretch"/>
	<Setter Property="HorizontalContentAlignment" Value="Stretch"/>
	<Setter Property="VerticalAlignment" Value="Stretch"/>
	<Setter Property="VerticalContentAlignment" Value="Stretch"/>
	<Setter Property="Template">
		<Setter.Value>
			<ControlTemplate TargetType="Intersoft:UXStackItem">
				<Grid x:Name="RootElement" Background="{TemplateBinding Background}">
					<Grid.Resources>
						<Style x:Key="EllipsisTooltipStyle" TargetType="Intersoft:StylishLabel">
							<Setter Property="Background" Value="Black"/>
							<Setter Property="BorderBrush" Value="{x:Null}"/>
							<Setter Property="BorderThickness" Value="1"/>
							<Setter Property="CornerRadius" Value="8"/>
							<Setter Property="Foreground" Value="White"/>
							<Setter Property="FontSize" Value="10.667"/>
						</Style>
					</Grid.Resources>
					<VisualStateManager.VisualStateGroups>
						<VisualStateGroup x:Name="CommonStates">
							<VisualState x:Name="Normal"/>
							<VisualState x:Name="MouseOver">
								<Storyboard>
									<DoubleAnimation Duration="0" To="1" Storyboard.TargetProperty="(UIElement.Opacity)" Storyboard.TargetName="AnimationElement"/>
								</Storyboard>
							</VisualState>
							<VisualState x:Name="Pressed"/>
							<VisualState x:Name="Disabled">
								<Storyboard>
									<DoubleAnimation Duration="0" To=".5" Storyboard.TargetProperty="Opacity" Storyboard.TargetName="ContentElement"/>
								</Storyboard>
							</VisualState>
							<VisualState x:Name="DisabledMouseOver"/>
						</VisualStateGroup>
						<VisualStateGroup x:Name="CheckedStates">
							<VisualState x:Name="Checked"/>
							<VisualState x:Name="Unchecked"/>
						</VisualStateGroup>
						<VisualStateGroup x:Name="SelectionStates">
							<VisualState x:Name="Unselected"/>
							<VisualState x:Name="Selected"/>
						</VisualStateGroup>
					</VisualStateManager.VisualStateGroups>
					<Border x:Name="AnimationElement" BorderThickness="{TemplateBinding BorderThickness}" CornerRadius="{TemplateBinding CornerRadius}" Margin="1" Opacity="0">
						<Border.Background>
							<LinearGradientBrush EndPoint="0,1" StartPoint="0,0">
								<GradientStop Color="#CCE2E2E2" Offset="0"/>
								<GradientStop Color="#CC8E8E8E" Offset="1"/>
							</LinearGradientBrush>
						</Border.Background>
					</Border>
					<Grid x:Name="ContentElement" Margin="{TemplateBinding Padding}" Visibility="Collapsed">
						<Grid Background="Transparent">
							<Grid.RowDefinitions>
								<RowDefinition Height="*"/>
								<RowDefinition Height="Auto"/>
							</Grid.RowDefinitions>
							<Grid Margin="4">
								<Border x:Name="ImageContainer"/>
								<Border x:Name="ContentContainer"/>
							</Grid>
							<Grid Visibility="Collapsed">
								<Intersoft:EllipsisText x:Name="GridTextElement" FontSize="{TemplateBinding FontSize}" FontFamily="{TemplateBinding FontFamily}" HorizontalAlignment="Center" Padding="6,2,6,2" Grid.Row="1" Text="{TemplateBinding Text}" TooltipStyle="{StaticResource EllipsisTooltipStyle}"/>
							</Grid>
							<TextBlock FontSize="{TemplateBinding FontSize}" FontFamily="{TemplateBinding FontFamily}" HorizontalAlignment="Center" Padding="6,2,6,2" Grid.Row="1" Text="{TemplateBinding Text}" TextWrapping="Wrap" VerticalAlignment="Center" Width="Auto" TextAlignment="Center"/>
						</Grid>
					</Grid>
					<Grid x:Name="StackElement">
						<Border x:Name="StackImageContainer">
							<Intersoft:ImageLoader x:Name="StackImageElement" ImageSource="{TemplateBinding Icon}" ProgressBarHorizontalAlignment="Stretch" ProgressBarVerticalAlignment="Bottom" ProgressTextVisibility="{TemplateBinding ImageLoaderTextVisibility}" ProgressBarMargin="15,0,15,14" UseAnimationOnParent="False" UseLoader="{TemplateBinding UseImageLoader}"/>
						</Border>
						<Border x:Name="StackContentContainer">
							<ContentPresenter x:Name="ContentPresenter" ContentTemplate="{TemplateBinding HeaderTemplate}" Content="{TemplateBinding Header}" HorizontalAlignment="{TemplateBinding HorizontalContentAlignment}" Margin="{TemplateBinding ContentMargin}" VerticalAlignment="{TemplateBinding VerticalContentAlignment}"/>
						</Border>
					</Grid>
				</Grid>
			</ControlTemplate>
		</Setter.Value>
	</Setter>
</Style>

In order to modify the grid item width, you could use the property StackGridItemWidth.

Based on my test with the RTM build of ClientUI, with the original snippet you posted on the first post the UXComboBox already show the name field in the dropdown result box.

Testing the code using ObjectDataSource I also encounter the same issue. I am still discussing this issue with the developer. Currently, as a workaround you will need to bind the individual column manually similar to client binding scenario.

I have just been informed that the update manager server will take some more time, probably in a few more days, before being updated to the latest build. However the WebUI 2010 R1 release is being slightly delayed and it will be release soon.

Because it will take some time for the update manager server to update the build, I suggest you download and install the WebUI 2010 R1and get WebGrid and WebDesktop build from the installation folder. This way you could retrieve the latest build faster. As I explained before, in this release WebGrid and WebDesktop does not have any major version upgrade.