Something

<Dim type="TopEdge">
<WidgetDim widget="__auto_TabPane__" dimension="TopEdge">
    <DimOperator op="Add">
        <AbsoluteDim value="4">
            <DimOperator op="Add">
                <PropertyDim widget="__auto_TabPane__Buttons" name="EnableTop">
                    <DimOperator op="Multiply">
                        <WidgetDim widget="__auto_TabPane__" dimension="Height">
                            <DimOperator op="Subtract">
                                <ImageDim imageset="WindowsLook" image="TabButtonScrollLeftNormal" dimension="Width">
                                    <DimOperator op="Add">
                                        <AbsoluteDim value="6" />
                                    </DimOperator>
                                </ImageDim>
                            </DimOperator>
                        </WidgetDim>
                    </DimOperator>
                </PropertyDim>
            </DimOperator>
        </AbsoluteDim>
    </DimOperator>
</WidgetDim>
</Dim>