Preg_Match(): compilation failed unknown property name

Xan is a georgian letter as I can find in Google, but it’s not a valid Unicode Script for RegEx, you can find a list of the Unicode Scripts here: http://www.regular-expressions.info/unicode.html

Maybe try using another one than Xan, maybe Georgian:

preg_match( '/[\p{Georgian}]/u', $content, $results );

Let me know how that goes.