This isn't really a problem rather a suggestion.
I tried 2.1 XML export at the top of the downloaded file there are few lines of instruction. Shouldn't users be reminded that when importing the new location should also be running 2.1? Step 5 ....be asked to map the authors .... will not work I guess if new location isn't running 2.1.
Also url reference should also be corrected (by find and replace) if users are moving content between sites, just a suggestion unless the above has already been covered in latest documentation.