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.
Same problem here ... and I can confirm that this only occurs when working directly in Word.
After your hint, I opened the file in OpenOffice, saved as XML, reopened in Word and saved directly docx (without making any changs). Thereafter everything worked as intended.
Would also need a fix for this ...