This is surely not a complete list of bugs. I'm documenting only bugs that are still active, not the numerous ones that have been gradually eliminated from the game since 1996.
I give the sea bugs first because, on the whole, they spoil the game more than the land bugs do.
- Fleets sent on amphibious assault sometimes attack the wrong port. In particular, Union assault fleets sent from Baltimore tend to attack Norfolk when ordered anywhere further south. If you try to avoid this by sending them from Atlantic City, they tend to attack Beaufort when ordered anywhere further south. This is a major problem for the Union player, and as far as I know it's a bug. I doubt that anything of the sort happened in reality. For this reason, it's useful for the Union to take Norfolk and/or Beaufort early if possible.
- Union amphibious assault fleets quite often run out of supplies for no apparent reason, despite having had plenty of supplies the turn before. This means, of course, that they have to abort the mission and return to base. Sometimes they run out of supplies without even leaving port, so the mission never gets started.
- Units sent on amphibious assault missions occasionally disappear without trace (the ships turn up empty). I've experienced this once; Martin James has suffered it six times in one game!
- Others have reported that, if you attempt several amphibious assaults starting from the same port on the same turn, some may not happen or may go to the wrong destination.
- If left in port doing nothing, Confederate warships tend to steam off on missions of their own devising. I think this happens only after European intervention, but I'm not completely sure. If necessary, they will automatically stock up with supplies for these missions. You have to watch them carefully, notice them putting to sea, click on them, and abort any unwanted missions.
- Sometimes fleets appear on the map as being in port when they're at sea, or vice versa.
- After European intervention, there are plenty of French and British troops shown waiting in garrisons at Nassau and St George, but it seems impossible to persuade these troops to do anything. As the Confederate player, I tried everything I could think of, but they remained stubbornly sitting in Nassau and St George throughout the game.
- When a Union fleet is patrolling a Confederate port, the fleet is shown on top of the port. However, if there's a Confederate fleet in that port, it's displayed on top of the Union fleet, which becomes invisible to the Confederate player. This could be easily fixed with a small change to the program: patrolling fleets should be displayed just outside the port, not on top of it.
- According to Rusty Coleman, after securing foreign intervention the Confederates can let the French have Sabine City, which then counts as a destination for cotton shipments.
- Also according to Rusty, fleet moves work better if you leave the speed set to normal and fleet moves set to visible.
- Artillery is completely, or almost completely useless in battle (though it is useful in sieges). I don't think this can be intentional; I think it must be due to a mistake in the battle calculations.
- Rusty Coleman discovered that it's possible to build up to 9 levels of fortification in a city in a single turn, by holding down the up arrow instead of just clicking on it.
- City garrisons sometimes disappear for no reason. Very occasionally, other strange disappearances of troops have been noted.
- Any unit with artillery only (no infantry or cavalry) will disappear. In one case when this happened to me, the artillery disappeared in Missouri and turned up later in a city garrison in Helena, Arkansas. But usually I think you never see it again.
- Brigades sometimes drop to a lower level of training. I don't know any reason for this, so I assume it's a bug. It seems to happen less often than in earlier versions of the game.
- The recruitment bonus is described by the manual and by the game itself as being paid per 500 men recruited, but experiment suggests that the true figure is per 100 men recruited (approximately). Thus, either recruitment costs are being wrongly calculated, or the information given about them is wrong.
- The morale figures in the battle analyses seem to make little or no sense. I suspect this is a bug Frank introduced recently while fixing some other problems with the battle analyses.
- The expected losses in the battle analyses ignore certain factors that may be important in calculating actual losses, such as fortifications and supply status. And I've once seen expected losses that were negative!
- The Confederate railway system normally operates with a dazzling efficiency that would have amazed the real Confederates. But sometimes it fails to work at all for no obvious reason. In particular, the direct line between Nashville and Chattanooga doesn't seem to work (as experienced by me and confirmed by Martin James). You can usually move between Nashville and Chattanooga by using the alternative line that passes by Decatur, but if that line is cut by the enemy you'll find that Nashville is no longer accessible by rail.
- Anecdote: I ordered an army of four divisions to move west from Washington to Strasburg. The army objective was given as Strasburg. In a single turn, all four divisions marched one hex south of Washington, then marched back to Washington, then repeated the same movement several times, becoming exhausted in the process, and finished up one hex south of Washington.
- Anecdote: I had a division stationed at Norfolk, and my opponent landed several divisions at Norfolk from the sea. For one turn, Confederate and Union troops coexisted peacefully at Norfolk: there was no battle. Inexplicable, as far as I know. Admittedly, it was the Christmas turn...
- According to Rusty Coleman, in some circumstances after unsuccessfully attacking a city it's possible to retreat your forces to any nearby city, including unoccupied enemy cities.
Supply bugs and oddities
- A nation's stock of supplies sometimes increases for no apparent reason, or moves between one region and another for no apparent reason.
- Rusty Coleman reckons that the stock of supplies sometimes decreases for no apparent reason. I haven't noticed this myself; if you notice it, he has a partial remedy: build plenty of forts to store your surplus supplies. You can then sell the forts whenever you need more supplies.
- According to Rusty, it's possible for state capitals to become isolated: he has experienced it. If so, this conflicts directly with the manual: “If a city is a state capital, the city is considered a supply source ... Supply sources and the units relying on them as a depot cannot be cut off from supply ...”
- A city on a navigable river always seems to be in supply, even if you capture a city a long way behind enemy lines and the only possible supply route passes through enemy-held cities. However, the enemy may sometimes be able to cut supply to the city by patrolling it with a fleet (doesn't always work).