I'm playing Whole Lotta Stratis version .74, single player, in the Scenarios section. I can go to game settings and set the difficulty of the enemy AI to expert and also use the slider to change difficulty. I save it and it stays saved.
Later I came back and tried to adjust the friendly AI difficulty and it wouldn't work. I can set the difficulty to expert, but it doesn't save. When I press OK nothing happens. I have to back out of the menu without saving changes in order to continue to play the game. I tried restarting my computer, but that didn't help.
FYI, I started a fresh game when I installed the latest version of the Alpha build.