Thanks for this. I'm running 10.13.6 and used your method. It sorta worked. I got to the pop up allowing the selection of AC or ACrossfire. Then I was asked to Allow XQuartz. It started the intro video. I hit escape to get to the main menu, but the screen turned and stayed black. The music was playing and the screen resolution was square shaped. I could move the cursor to the edges. Sadly, the only way out of the program was to shutdown the computer.
Then I let the movie play through. It backed out to another pop up asking me to Allow XQuartz to change the screen resolution. I did, and I go the the menu screen and selected a new game. It started and worked! I've been sad for months!!!
I'll try later to see if I can skip the video.
Just spent an hour trying to fix it or find another way to play it. Was hoping I could get it to work on my MBA instead of my Windows Desktop (because playing SMAC in bed sounds like the best thing ever). Sadly, not to be.
Um. Yeah is there any chance this will be updated at some point for Mojave or should I just give up and play on Windows?
i managed to get it working by modifying an option in the Wineskin.app inside the main app of the game.
It's pretty easy:
Go to Applications in Finder, right click on Sid Meier's Alpha Centauri Planetary Pack.app, choose Show Package Contents, and then double click on Wineskin.app. Then go to Advanced -> Options and check the last option: Force use of system installed XQuartz... and the close the app.
It works for me, good luck!