Please note this is an old forum thread. Information in this post may be out-to-date and/or erroneous.
Every phpdocx version includes new features and improvements. Previously unsupported features may have been added to newer releases, or past issues may have been corrected.
I changed our regex to the following and it's working well now...
'\{\{[^}]+\}\}'
That's s till too permissive for us, but you put me on the right track to find what my previous regex was missing. maybe newlines? idk I'll keep exploring.