В файле /templates/demooldschool/xslt/modules/webforms вот что:
<?xml version="1.0" encoding="UTF-8"?>
<xsl:stylesheet version="1.0"
xmlns="http://www.w3.org/1999/xhtml"
xmlns:xsl="http://www.w3.org/1999/XSL/Transform"
xmlns:date="http://exslt.org/dates-and-times"
xmlns:udt="http://umi-cms.ru/2007/UData/templates"
xmlns:xlink="http://www.w3.org/1999/xlink"
exclude-result-prefixes="xsl date udt xlink">
<xsl:template match="result[@module = 'webforms'][@method = 'page']">
<xsl:apply-templates select="document(concat('udata://webforms/add/', //property[@name = 'form_id']/value))/udata" />
</xsl:template>
</xsl:stylesheet>