<Window x:Class="ProcTest.MainWindow"
        xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
        xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
        Title="MainWindow" Height="350" Width="525" xmlns:igDP="http://infragistics.com/DataPresenter" Loaded="Window_Loaded">
    <DockPanel LastChildFill="True">
        <Button Name="m_preview" Content="Preview" DockPanel.Dock="Bottom" Width="60" Margin="5" Click="m_preview_Click"    />
        <igDP:XamDataGrid Name="m_grid" />
    </DockPanel>
</Window>

namespace ProcTest
{
    /// <summary>
    /// Interaction logic for MainWindow.xaml
    /// </summary>
    public partial class MainWindow : Window
    {
        public MainWindow()
        {
            InitializeComponent();

            m_grid.DataSource = GetData().DefaultView;
        }

        private void Window_Loaded( object sender, RoutedEventArgs e )
        {
            FieldLayout field_layout = m_grid.FieldLayouts[ 0 ];

            foreach( Field field in field_layout.Fields )
            {
                if( field.DataType == typeof( Double ) )
                {
                    SummaryDefinition summary = new SummaryDefinition();

                    summary.Calculator = null;
                    summary.Key = field.Name;
                    summary.SourceFieldName = field.Name;
                    summary.Calculator = SummaryCalculator.Sum;

                    field_layout.Settings.GroupBySummaryDisplayMode = GroupBySummaryDisplayMode.SummaryCellsAlwaysBelowDescription;

                    field_layout.SummaryDefinitions.Add( summary );
                }
            }
        }

        private void m_preview_Click( object sender, RoutedEventArgs e )
        {
            Preview viewer = new Preview();

            viewer.PrintPreview( m_grid );
        }

        private DataTable GetData()
        {
            DataTable data = new DataTable();

            DataColumn col1 = new DataColumn( "date", typeof( DateTime ) );
            DataColumn col2 = new DataColumn( "desc", typeof( string ) );
            DataColumn col3 = new DataColumn( "n1", typeof( double ) );
            DataColumn col4 = new DataColumn( "n2", typeof( double ) );
            DataColumn col5 = new DataColumn( "n3", typeof( double ) );

            data.Columns.Add( col1 );
            data.Columns.Add( col2 );
            data.Columns.Add( col3 );
            data.Columns.Add( col4 );
            data.Columns.Add( col5 );

            for( int j = 0; j < 3; ++j )
            {
                DateTime date = DateTime.Today.AddDays( j );
                string desc = "test" + j;

                for( int i = 0; i < 3; ++i )
                {
                    DataRow row = data.NewRow();
                    row[ col1 ] = date;
                    row[ col2 ] = desc;
                    row[ col3 ] = i;
                    row[ col4 ] = i + 10;
                    row[ col5 ] = i * 10;

                    data.Rows.Add( row );
                }
            }

            return data;
        }

    }
}

Print Preview window:

<Window x:Class="ProcTest.Preview"
        xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
        xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
        Title="Preview" Height="300" Width="300" xmlns:igReporting="http://infragistics.com/Reporting">
    <DockPanel>
        <igReporting:XamReportPreview Name="m_preview" />
    </DockPanel>
</Window>

namespace ProcTest
{
    /// <summary>
    /// Interaction logic for Preview.xaml
    /// </summary>
    public partial class Preview : Window
    {
        public Preview()
        {
            InitializeComponent();
        }

        public void PrintPreview( XamDataGrid grid )
        {
            Report report = new Report();

            EmbeddedVisualReportSection section = new EmbeddedVisualReportSection( grid );

            report.Sections.Add( section );

            m_preview.GeneratePreview( report, false, true ); 

            ShowDialog();
        }
    }
}

Snapshot of grid - summary columns correctly aligned:

 Snapshot of Print Preview - summary columns all shifted:

HI,

I can see the way the way the summaries line up in your grid and in the print preview but I need more  information about how you are creating the summaries in the grid.  It would be helpful to have a small sample. 

What version of NetAdvantage are you using?  And what service release version?