don't get me started...

Now here's an idea for any software developers - grab AutoIt (is it still around?) and make a quick script called "typical_user" that automatically clicks "Yes" (or similar) on any dialogs that appear. Now, run this in the background while testing the UI of your software :)

Edit: Yes, AutoIt still exists! http://www.autoitscript.com/site/autoit/

Or try http://www.sikuli.org/

For automation, it's replaced AutoIt in my toolbox - just in case I get another contract in the future like one of these.

OSX warns you when you change the file extension too, though it doesn't warn that it may not work, it just says it'll open in a different application.

Did you read that EULA then?