This version of OREMO is the latest Mac native version. The Japanese app came from the official release page here.
If you open the app and the file paths for the reclist, folder, etc. are extremely long and look messed up, it's because of a new security feature in Sierra. Move the folder anywhere outside of Downloads.
If that doesn't work, open Terminal, and type this in.
(Substitute "path/to/" with the actual file path, such as "Users/KLAD/Downloads/oremo-mac-2.0-b110812-p1/oremo.app")Code:xattr -dr com.apple.quarantine path/to/oremo-mac-2.0-b110812-p1/oremo.app
I've left all the settings at default, so you will have to change the colors yourself and download your own reclists.
Because this is a Mac native app, you are able to use unicode reclists. Letters with accent marks, Korean hangul, the list goes on. Unicode samples and aliases are also compatible with UTAU-Synth.
Strings were translated to English based on the translation of the Windows version of OREMO, and some Google Translate. Overseas terminology was preferred over direct translations (ex "OTO" instead of "voice configuration"). I'm not fluent with Japanese, so feedback is welcome.