This add-on is not compatible with XF 2.1.
It worked fine for me on the release version of 2.1.
Did a great job converting old AME BB Codes from vBulletin to media bb codes for XenForo.
I got many of the regex's and instructions to use from this old thread. Do note you need to run them once with http and again with https as you may have a mix of URLs used on your forum. At first I edited the regex to do both http and https at the same time but it proved too much memory for my server. As it was I had to increase my PHP memory limit temporarily by adding this line to the top of the /src/config.php file:
Still have more to convert but it's working, Made the conversion much better!