Hi Leo,
Ah, I think that we changed the root element on that example to be <form>, as it is on all forms, so the XPath expressions in the trigger should be /form/details/title and /form/details/author (instead of /book/…). Could you try with those updated expressions? And you can also look at the XML in the tool you're using, to see if the XPath expression is correct. You'll let me know if this works for you, and I can then fix the doc accordingly.
Alex
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