Summary: I cannot overstate how crappy it is that this game forces you to use Steam. Warning to Mac users: Steam is a PC platform. It has been "adapted" to Mac and other platforms in a very slap-dash way that shows they don't really give a crap. As a result, it is buggy. You get random error messages, buttons don't have text on them, text is buried under overlapping windows so you can't read the info you're supposed to.
Summary: This product was advertised to be compatible with Ubuntu 12.04. It is not. It does not run. I bought this product for my kid. We do not have Windows, only Ubuntu, and so I researched it before buying to verify compatibility. Installing the game is like a game in that you first have to get an account on 'Steam' - a intermediate layer that allows software to run on multiple operating systems. You have to get the account, then download and install it.
Summary: Warning: It's very addicting. You will spend hours seeing if your choice of strategy is geopolitically viable. If you've played EU III, the new mechanics will take a little while to get used to, but in the end, I prefer them with just a few exceptions; 1) fewer strong/playable countries at the beginning 2) Loss of ~50 years of play time Improved: 1) Obnoxious ship boarding times 2) Coring 3) Manufacturing of CBs 4) No problems with playability of large nations b/c...
Summary: I've played a lot of Crusader Kings II and never the EU games, so this is my first installment. I love the strategy and depth of it. It was incredibly complicated at first, I was so lost and confused on what I needed to do and how to do it, but it comes with a nice tutorial in the game, plus on Steam, there are quite a few helpful guides to read for newbies like myself. I love the grand scale of the game and will be playing it for a long time to come.