Installation for Mac is basically the same as Windows.
1. Go to Steam library.
2. Right click Unturned and click properties, then click local files at the top. Then browse local files.
3. Right click the Unturned app and click show package contents. Then Double click contents.
4. Double click Data, then Managed.
5. Right click on Assembly-CShard.dll inside managed and click Duplicate.
6. Replace the Hacked Assembly-CSharp.dll with the old one.
7. Done.