Docx4j Convert to PDF, FOP Issues/ Cannot perform the transformation error

Docx4j Convert to PDF, FOP Issues/ Cannot perform the transformation error

Docx4j version 2.8.1.3
The docx is a very simple one with just some text, it doesn't seem to work
for any docx though.
May be easier to view source/exception at docx4j forums.
http://www.docx4java.org/forums/pdf-output-f27/docx4j-to-pdf-fop-issues-cannot-perform-the-transformation-t1652.html
If answered at one place I will update both with answer
Here is the exception
fourseasons.general.conversionservice.converter.AbstractConverter FOP issues
org.docx4j.openpackaging.exceptions.Docx4JException: FOP issues
Caused by: org.docx4j.openpackaging.exceptions.Docx4JException: Cannot
perform the transformation
at org.docx4j.XmlUtils.transform(XmlUtils.java:911)
at org.docx4j.XmlUtils.transform(XmlUtils.java:802)
at
org.docx4j.convert.out.pdf.viaXSLFO.Conversion.output(Conversion.java:349)
... 230 more
Caused by: javax.xml.transform.TransformerException:
java.lang.NullPointerException
at
org.apache.xalan.transformer.TransformerImpl.executeChildTemplates(TransformerImpl.java:2405)
at
org.apache.xalan.templates.ElemLiteralResult.execute(ElemLiteralResult.java:1376)
at
org.apache.xalan.templates.ElemApplyTemplates.transformSelectedNodes(ElemApplyTemplates.java:395)
at
org.apache.xalan.templates.ElemApplyTemplates.execute(ElemApplyTemplates.java:178)
at
org.apache.xalan.transformer.TransformerImpl.executeChildTemplates(TransformerImpl.java:2400)
at
org.apache.xalan.transformer.TransformerImpl.applyTemplateToNode(TransformerImpl.java:2270)
at
org.apache.xalan.transformer.TransformerImpl.transformNode(TransformerImpl.java:1356)
at
org.apache.xalan.transformer.TransformerImpl.transform(TransformerImpl.java:709)
at
org.apache.xalan.transformer.TransformerImpl.transform(TransformerImpl.java:1273)
at
org.apache.xalan.transformer.TransformerImpl.transform(TransformerImpl.java:1251)
at org.docx4j.XmlUtils.transform(XmlUtils.java:909)
... 232 more
Caused by: java.lang.NullPointerException
at
org.apache.xalan.templates.ElemVariable.getValue(ElemVariable.java:282)
at
org.apache.xalan.templates.ElemVariable.execute(ElemVariable.java:248)
at
org.apache.xalan.templates.ElemApplyTemplates.transformSelectedNodes(ElemApplyTemplates.java:395)
at
org.apache.xalan.templates.ElemApplyTemplates.execute(ElemApplyTemplates.java:178)
at
org.apache.xalan.transformer.TransformerImpl.executeChildTemplates(TransformerImpl.java:2400)
Code to create the bytes:
Mapper fontMapper = new IdentityPlusMapper();
wordmlPackage.setFontMapper(fontMapper);
org.docx4j.convert.out.pdf.viaXSLFO.Conversion c = new
org.docx4j.convert.out.pdf.viaXSLFO.Conversion(
wordmlPackage);
ByteArrayOutputStream os = new ByteArrayOutputStream();
c.output(os, new PdfSettings());
os.close();
binarypdf = os.toByteArray();