We have checked all your files and can't reproduce the encode issue. Could you please remove the files cache and recheck your browser setiings with encoding. As you can see on these screenshots (http://prntscr.com/9qff8nhttp://prntscr.com/9qfff9 ) that .doc files is rendered well. But with .xlsx file, we have reproduced some incorrect rendering issue with the rows (http://prntscr.com/9qfj4p).
We have logged the issue in our issue tracking system and will notify you when it will be resolved.
Note: the rendering of 5M.docx and Xlsx_TEST.xlsx files took longer time than 1M.doc