Hello,
We have opened both DOCX using MS Word 2010, MS Word 2013 and MS Word 2016 and resaved them and in all cases, the chart is the same.
Some versions of MS Word may do minor adjustments when saving (such as margins or colors), but they shouldn't change the document drastically.
If you send to contact[at]phpdocx.com the DOCX before and after being saved using your version MS Word we'll check them to find what changes have been applied.
Regards.