This theme is compatible with Mac OS X. However, I do not own a (physical) Mac, so support may be limited. Please contact me via e-mail if you see any issues with the theme on Mac OSX. Thanks
Regarding Australis support:
First of all, don't worry, I won't stop developing the theme, but at least it will be a lot harder to maintain. Australis did away with several icons and buttons, which i'm trying to restore by including a customizer add-on with the theme (just like Classic Compact). Check the GitHub page to see if any beta versions are available.
Donations are welcome. (DOGE too!)