TYPO3 Core

Added this flexform configuration for rendering fal images . But give me an alert with 500 Internal error . My Typo3 version is 7.6.3. Can any one please confirm this ?

<config>
    <type>inline</type>
    <foreign_table>sys_file_reference</foreign_table>
    <foreign_field>uid_foreign</foreign_field>
    <foreign_sortby>sorting_foreign</foreign_sortby>
    <foreign_table_field>tablenames</foreign_table_field>
    <foreign_match_fields>
        <fieldname>imageBackground</fieldname> <!-- CAUTION!! Replace "fal" with the variable name of this field! -->
    </foreign_match_fields>
    <foreign_label>uid_local</foreign_label>
    <foreign_selector>uid_local</foreign_selector>
    <foreign_selector_fieldTcaOverride>
        <config>
            <appearance>
                <elementBrowserType>file</elementBrowserType>
                <elementBrowserAllowed>gif,jpg,jpeg,tif,tiff,bmp,pcx,tga,png,pdf,ai</elementBrowserAllowed>
            </appearance>
        </config>
    </foreign_selector_fieldTcaOverride>
    <foreign_types type="array">
        <numIndex index="2">
            <showitem>--palette--;LLL:EXT:lang/locallang_tca.xlf:sys_file_reference.imageoverlayPalette;imageoverlayPalette,--palette--;;filePalette</showitem>
        </numIndex>
    </foreign_types>

    <minitems>0</minitems>
    <maxitems>99</maxitems>

    <appearance>
        <useSortable>1</useSortable>
        <headerThumbnail>
            <field>uid_local</field>
            <width>45c</width>
            <height>45</height>
        </headerThumbnail>

        <showPossibleLocalizationRecords>0</showPossibleLocalizationRecords>
        <showRemovedLocalizationRecords>0</showRemovedLocalizationRecords>
        <showSynchronizationLink>0</showSynchronizationLink>
        <useSortable>1</useSortable>
        <enabledControls>
            <info>1</info>
            <new>0</new>
            <dragdrop>0</dragdrop>
            <sort>1</sort>
            <hide>1</hide>
            <delete>1</delete>
            <localize>1</localize>
        </enabledControls>

        <createNewRelationLinkTitle>LLL:EXT:cms/locallang_ttc.xlf:images.addFileReference</createNewRelationLinkTitle>
    </appearance>

    <behaviour>
        <localizationMode>select</localizationMode>
        <localizeChildrenAtParentLocalization>1</localizeChildrenAtParentLocalization>
    </behaviour>
</config>