If you already tried that and now 1.23.1 won't launch, something may have gone wrong with the chmod command. That said, if you're trying to avoid KFX, then you need to run chmod -x per Method 2 in the first post. High Sierra (10.13) and Mojave (10.14) can still run 32-bit apps. The 64-bit requirement is only an issue if you're running Catalina (10.15), which hasn't been released yet except in beta. Kindle for Mac 1.23.1 should run on High Sierra without having to do anything extra or special. What's the exact error message you're getting?
Is there something I need to do in order to successfully run 1.23.1 (or 1.17!) on this Mac?. Downloaded 1.23.1 from the link given at the pinned post at the top of this thread. I couldn't run Kindle 1.17 for Mac on High Sierra (10.13, to which I just updated) - got the 'need to update file type' message (assume that means 64-bit files), and the app won't even launch.
