OK, for versions of 1.5 and later it should work fine just to download the latest version and replace your old version’s OpenEarsDistribution folder with the new version.
The only other thing to consider is that if, when you originally followed the tutorial installation instructions, you chose to copy the OpenEarsDistribution/Framework folder contents into your project, you may also have the contents of the OpenEarsDistribution/Framework somewhere else in your project and being referenced from that place, in which case you should also replace them with the contents of the current OpenEarsDistribution/Framework folder. So, as an example, if items like AcousticModelEnglish.bundle or Slt.framework or OpenEars.framework are in the root folder of your app project as well as being wherever you downloaded your first OpenEarsDistribution download to, drag the contents of the Framework folder in the current OpenEarsDistribution download into that root folder of your app project to write over them.
The goal is just to replace the old files wherever they reside and are being referenced from by your app with the new ones which are found inside of the current distribution’s Framework folder.
When everything has been done correctly, that first line of OpenEarsLogging should read 1.71.