I'm on a MacBook Pro with Mac OS X v. 10.6.8. I purchased the game through Steam, and Episode 2 downloaded via Steam the moment it became available.
It seems downloading Ep 2 wiped out my saved games, so at the start of Ep 2, the game said it would randomize events.
Also, found that the mouse was not working, and moving the crosshairs over the points of interest was downright impossible. I could go extremely high or low, so it was virtually impossible to interact with the points of interest.
I then decided to see if the issue was with Ep 1. Ep 1, interestingly, had me look in the police car's rear view mirror. I don't know if that is some form of mouse calibration. After shooting the officer in the head, I quit the game and ran Ep 2, and interestingly enough, the mouse worked fine afterwards.
I'm a little disappointed at the inability to continue the game path I originally played. I saved over all 3 slots, trying different scenarios, the last one being Doug being alive instead of the reporter. Interestingly, in Ep 2, Doug is around, so I'm not 100% if choices carry over from episode to episode or not.