i am applying custom format like this, with the latest service this one goes for a task and whole application hangs. Please check.

  <ig:NotContainingConditionalFormatRule.StyleToApply>
                                <Style TargetType="ig:CellControl" >
                                    <Setter Property="Style"  Value="{StaticResource GridCellStyle}" />
                                    <Setter Property="Background" Value="#FFB5FF00"  />
                                </Style>
                            </ig:NotContainingConditionalFormatRule.StyleToApply>