I have downloaded the game (twice) and after it opens I see 3 files: I have tried to open each one and either get a "set up has failed to detect a base game" message or I am given a small window which says "select an app to open this file".....I have no idea what any of those opt...

I've just purchased the game...download plus disc (which hasn't arrived yet). Thought I had downloaded it okay...read entire manual (which downloaded just fine)...but when I went and clicked on"Play" nothing happens...need some help.