I'm sorry, but the application installation process is just broken on macs. Yes, broken. No, I don't mean NOBODY can figure it out, just that it is utterly unintuitive and way, way, way, way, way, way too complicated. In fact, it goes against the entire Apple philosophy of shielding the user from unnecessary exposure to low-level processes. It is rather more like the (bad) approach of (*some*) linux developers who delight in nerdy fiddling at a very deep level of OS involvement. Sure, it can give you a lot of power (as can the command line), but there's a reason why Apple avoids that as a default. It is actually a very lazy way out for developers - any moron (I'm exaggerating, can you tell

) can develop something that gives a lot of power, and any moron can develop something that's simple to use but not very powerful. Only the GREAT designer can make something that is BOTH powerful AND simple to use.
Uncharacteristically, for Apple, they've fumbled the app installation paradigm in macs. It's stupid. For crying out loud, WHY would you want to complicate this PARTICULAR process? It's not like the different aspects of installing apps in macs gives you somehow vastly different options... so what is the benefit of making it complicated? Why pay the heavy price of confusion and an ugly unintuitive process... for WHAT?
You gotta be honest. Mostly Apple gets things right where Windows does not. Mostly. That's why I've switched platforms. But every once in a while the "other" platform gets something right (hey, even a broken watch is right twice a day!). It is quite, quite clear that the program installation process in window is vastly superior (though hardly perfect!) to Apple. Hurts to say it, but it's the truth.
Again, I'm not saying it's impossibly difficult in Apple, but it certainly is more complicated (for what good reason... none), and harder to grasp. I am STILL confused by it after many weeks. It took me almost no time to learn the rest of the platform (so far!), but this... just sucks. Sorry.