AoM Gold edition won't start on Mac on newest OS

So a bunch of my friends usually get together to play AoM and so far, it's always worked fine. Last time, the game wouldn't start for some of us. Those with the problem all had the newest OS, Mac High Sierra 10.13.x installed.

We all used a "Age of Mythology Gold.app" and worked for everyone with an OS older than High Sierra 10.13.

Suggestions for fixes welcome!