Most OS X apps can have their interface elements accessed by AppleScript, and so anything can be scripted. Unfortunately, not all apps use an Aqua interface, especially games with game-engine-rendered interface elements. This means AppleScript can't find buttons, etc., to click on, and you're out of luck trying to automate actions.
Recently, I was given the unpleasant task of automating actions in such unfriendly apps. I just about went crazy trying to find a way to write a simple script with coordinates for mouse click events.There's nothing available within AppleScript for pushing the mouse around, and I couldn't find any command-line utilities either. Out of necessity, I wrote my own.
This is my first time writing anything that even resembles Cocoa, and my first time writing code that compiles in nearly 10 years. I'm a scripting guy, and I just wanted to be able to write a script. What I wrote is a little command-line app called click that invokes CGPostMouseEvent from the CGRemoteOperation.h header file. It takes coordinates as command line arguments, moves the mouse to that position, then clicks and releases the mouse button. I think this could even be modified to click, hold, and drag, but I haven't taken it that far because I don't need to. Here's the source:
Mac OS X Hints
http://hints.macworld.com/article.php?story=2008051406323031