Has anyone else had issues with DEFCON on macOS Sierra? I can' even get the game to open now...

Same for me. When I launch the single player version, the screen goes black, then returns to the desktop.

I have the same issue. I note from the Ambrosia website this game was originally designed for PowerPC/Intel and OSX 10.3.9 .. I'm thinking it simply may not work on Sierra :/

Like I said it was PowerPC *and* Intel. This means it used Rosetta.

The same here: I'd like to know if they will fix this sooner or later or if we do ned to ask a refund.
It seems there's no way to write a mail for this kind of issues... what will you do next?

No, that would mean it's a Universal App and should work on either PPC or Intel. Also, looks that Rosetta was dropped with 10.7 not 10.6. Does not compute (launching issue/crashing issue): https://www.gog.com/support/contact/technical_issues_with_games/defcon

Thank you!

Here the solution the guys from GoG gave to me:
"Please download the archive from here:
[SEE ATTACHED IMAGE]

Please right-click the game's app and select to Show Package Contents, please go to Contents > Resources > game > dat, right-click the game's app and select to Show Package Contents, go to Contents > Frameworks and replace the SDL files with the ones from the archive."

now it works.

Thank you for providing that solution, but is there any way you can just post the link? I typed it in exactly and just got a 404 error.

NVM haha, sorry I am not too savy on Macs.

Having the same problem. The file referred to above can't be found - error message. What do I do?