The new version has two different games in it. The classic rules are exactly those of this older edition excet for rewordings for clarification. You can download those rules from here on BGG and they ought work fine. Just keep in mind that CotE2 is a different game.

No you cannot really use the new rules. The difference is that the new rules use a different type of combat dice. I suppose you could adapt your dice to use them, but the battles are MUCH worse...from a wargaming point of view (I suppose if you are a pure Eurogamer who hates combat, war economics, and all that, you might like the new rules...personally, the new combat rules may be balanced according to some...but they REALLY stink...like excessively badly. I've only ever had ONE rating that was a 1 in relation to the entire game, though not CotE, it was the game ATTACK! upon which CotE new combat rules are based...if that tells you anything).

However, to do that, basically have two sides equal an infanty, one side equal a cavalry, one side equal a catapult, one side equal a galley, and I believe one side is blank. If you use that adaptation (probably 1/2 = Infantry, 3= Cavaly, 4=Catapult, 5=blank, 6=Galley), you could use the new rules. Not that they are any good.

For CotE II, which is a completely new game, and actually worth the money of the new version, you would need some of the components that come in the new version, mainly the cards, and probably the tokens which indicate your influence. I don't think there's any way to adapt it. It uses the same combat method as the first one, which means I still hate the "combined arms...all troops are equal in power, even if you pay 250 gold for a catapult but only 5 for an infantry...method of battle, but the rest of the game is rather fun to play.

I actually believe the original game is the best of the bunch. Love it to death. Pity that you didn't find it all that interesting.

I think if you didn't like the original because you prefer Eurogames, then I think you WOULD love the new version WITH CotE II rules (which as I said, is a completely different game and really in no way related to the original game. It is actually based upon Struggle of Empires, another game which is fun as well.). However, you would probably still dislike the Classic/orginal game rules even with their "improved" version of combat.