2016 is no longer sold by TurboTax or supported. I don't know what you mean the "unarchive" program, a download should be a .dmg file that the Mac should automatically open and present an install window to drag the application to the applications folder.
I don't know where you purchased the download that is not available from TurboTax, but it sounds like it might be a bootleg copy.
**Disclaimer: This post is for discussion purposes only and is NOT tax advice. The author takes no responsibility for the accuracy of any information in this post.**
