The Romance of the Three Kingdoms games were always a little rough-hewn, but managed to succeed nonetheless because of their depth and content. They offered sweeping strategy gaming set in the politically charged atmosphere of China's Warring Kingdoms epoch, with a rich cast of characters and solid gameplay. In each, you played leader of a kingdom, responsible for raising and equipping armies, capturing other cities, increasing the wealth and happiness of your citizens, and forging alliances with other leaders, each with their own unique characters. The goal is to bend all of China under your yoke.
The series pretty much hit its stride with the third release; Romance of the Three Kingdoms IV: Wall of Fire pushes it a little further than it needs to go, for a number reasons. Frankly, the interface was never great, and Koei has only made it more cumbersome and confusing by piling on a heap of new details. This is exacerbated tenfold by the total lack of printed documentation or even the most basic tutorials. The help functions are poorly written, and doping out the commands is an exercise in futility, even for people familiar with the previous games.
The native Windows support is nice, but adds little more than slightly movable windows. Graphics are better this time around, but still aren't up to contemporary standards. Castle sieges are really the only positive element: Little armies place little ladders on your castle and attempt to scale the walls as you fend them off. It's nifty, but hardly enough to carry the day.
In the end, this game will leave you with a strong sense of déja vu. You've played Romance of the Three Kingdoms, in better incarnations, already; there's not much reason to play it again.