Transforming a perfectly valid (and stripped-down) TEI Corpus document to XSL-FO generates a fiel with two elements fo:root which is of course not well-formed. See the attached result FO file generated by xml/tei/stylesheet/fo2/teiCustom.xsl applied to:
<?xml-model href="http://www.tei-c.org/release/xml/tei/custom/schema/relaxng/tei_corpus.rng" type="application/xml" schematypens="http://relaxng.org/ns/structure/1.0"?>
<teiCorpus xmlns="http://www.tei-c.org/ns/1.0">
<teiHeader>
<fileDesc>
<titleStmt>
<title>title of corpus</title>
<author>author</author>
</titleStmt>
<publicationStmt>
<p>Publication Information</p>
</publicationStmt>
<sourceDesc>
<p>Information about the source</p>
</sourceDesc>
</fileDesc>
</teiHeader>
<TEI xml:id="MyTextNumber1">
<teiHeader>
<fileDesc>
<titleStmt>
<title/>
<author/>
</titleStmt>
<publicationStmt>
<p/>
</publicationStmt>
<sourceDesc>
<p/>
</sourceDesc>
</fileDesc>
</teiHeader>
<text>
<body>
<div>
<p/>
</div>
</body>
</text>
</TEI>
<TEI xml:id="MyTextNumber2">
<teiHeader>
<fileDesc>
<titleStmt>
<title/>
<author/>
</titleStmt>
<publicationStmt>
<p/>
</publicationStmt>
<sourceDesc>
<p/>
</sourceDesc>
</fileDesc>
</teiHeader>
<text>
<body>
<div>
<p/>
</div>
</body>
</text>
</TEI>
</teiCorpus>
I hate teiCorpus and I hate XSL FO :-{
still I will make this do something
I have tested the teiCorpus with HTML, LaTeX and FO and all now perform as expected