To install, upload the contents of the upload folder into your OpenCart root folder.
This version includes a fix for OpenCart's 3 digit currency limitation so you can use currencies with more than 3 digits like DOGE, NOBLE, and MINT. If you want to list items in those currencies directly use the currency codes DOG, NBL, and MNT respectively.
You can still use the full 4 digit code for the "Symbol Right" setting so your users probably won't even notice the change.