Although Molflow is developed for Windows, the WineSkin wrapper allows running it on Mac in non-native mode with a slight performance overhead. You can give it a try through the Downloads section and let us know how it works.
Known issues:
- In Global Settings, all processes will be marked "Dead". This is a permission problem.
- The ALT key is remapped to the Mac option key. That said, some combos (ALT + scroll zoom, for example) don't work.
UPDATE, 2018.11: There is now a fully functional, native Mac version for Molflow. You find it in the downloads, please read the instructions to run it.