Port improvements are independent of technology. Any port may have forts and shipyards of any size. Shipyards allow shipbuilding and major repairs, their size determines which number and types of ships may be built. Usually, ships have to reserve movement points for the return trip. The latter type of movement may even double the usual range if a stopover is made at a base.
Battles are resolved rather prosaically, in normal artillery combat there is no random element.
Both sides fire simultaneously. An optional rule of the extension set allows to take artillery ranges into account. That's all there is to the game- rather enough to weigh heavily upon your mind even if the rules themselves are not complicated. They raise the game above games like Risk and Diplomacy. I can't really say a lot about strategy and tactics by now.