By "activated it in the mods menu" do you mean checked it, and clicked apply? Which results in the game exiting.
To get logs, run the game from a shell prompt. it outputs to the shell all the messages. If there's no Random Portrait button, then the mod did not apply correctly. You might need to extract a fresh copy of the game, and apply the mod again, thus time running it from the shell, to see what errors might happen. Some errors are normal though, so if anything can be worth while to run the game, and exit it once, just to see what normally happens. Then run it again, apply the mod, and see if any different errors appear. I don't know if mods work on Mac as I haven't read of anyone trying and my only mac is a work laptop.
The game has it's own random portrait code, but it *only* uses race, so that's likely what you saw get applied.