If it's a glitch, it has never been documented and we would need it documented. I started up a game and built some wonders. I made a save the turn before my first great person, and played around with settings. Even with all three related options checked (units auto-promote, workers start automated, and missionaries and executives start automated), I could not get a great person to spawn automated. Furthermore, when the great person unit is selected, there is no "automate" option. In conclusion, either your girlfriend clicked a button she didn't know she clicked, or there's some deep glitch. Have her start a game on easy mode just to build a wonder (Arabians start with mysticism), and see what happens. Maybe send her a save-game, or have her reinstall. I'm having a tough time rationalizing that she has some weird hardware issue that civ4 is suddenly obsolete.

Executives work like missionaries. The five refers to the number of executives you can have at the same time. when you send them to a city, they spread their corporation to that city, giving the city the effects of the corp and the founder of the corp a gold bonus. This costs a lump sum of gold, which is increased if the city already has another corp in it. So, this may be one cause of your problem, you don't have the gold to spread the corp. Execs are unable to expand their corp in a city if the city already has that corporation or if it the headquarter of a competing (=uses the same resources) corp (denoted by the star next to the corp icon). Also, if a civ uses the state property (affects all corps) or mercantilism (affects only foreign corps) civic corporations are severly hindered, I can't remember whether the corp cannot spread in the cities at all or if those civics prevent the effects of the corp. Corporations can only be founded by a great person.

No, you won't get a civ's techs automatically, if you conquer it. You can negotiate some techs "in bundle" with the capitulation/peace treaty deal, but from the conquest itself it doesn't follow that you'll get any techs at all.

They have a pre-made AI personality script, that gives them their unique behaviour. To give an example, Catherine is the only leader that might declare war on you even if you have the best (Friendly) relationship, other leaders will never do this. She is the backstabber. Of course this behaviour will also match their traits more or less, so Montezuma, Shaka or Napoleon are more likely to go into war (actually you will see them fighting most of the time), while Hatshepshut, Gandhi or even Mansa Musa will attack you quite rarely.

The AI city placement suggestions are based on the same algorithm AI players use to choose the location of their cities. This algorithm is not optimal of course, you can feel it when you conquer an AI civilization's cities and worry about their placement. It is outstandingly weak in using coastal cities, building cities one tile from the coast, even with a Financial leader (also resulting in a weaker navy and missing the health that Harbors give). I think you should take the city placement advice of the AI as you would take any advice: a possible alternative. When you are deciding on the placement of your cities, you have to take several alternatives into account and weigh them, because city placement is vital. Also, there are some strategical points that sometimes override general city placement rules. Sometimes, you just want to close down a bigger peninsula from the AI by putting a city in the enter point (and not having open borders). Sometimes, you want to get a strategical resource a few rounds earlier, so you put your city on the resource because that few rounds can mean a war won. Sometimes you can put the city in a location where it connects two oceans, giving you a quick route. The AI city placement can be turned off as well, but I normally leave it on, just to see one more alternative I did not think of.

Honestly speaking, I do not remember 100%, but as far as I remember, you get this penalty on a war declaration and it remains even after the civ is destroyed. I would bet on this.

Yes, you will. Additionally you'll also get a "you traded with our worst enemy" penalty in much the same fashion . The latter being more frequent, as it is unlikely to go to war without having met all civs on the continent.

This is one of several random events that were added in the Civ IV expansion -- the prairie dog event in particular means that one of the Babylonian tiles has, randomly, received +1 Commerce.

Beyond the Sword includes all new gameplay elements added in Warlords, including Great Generals, vassal states, A.I. improvements, new Civilizations, etc. The only thing that Beyond the Sword is missing are the 8 game scenarios that came with Warlords. So basically, unless you really want to play the specific scenarios that came with Warlords, you're safe going straight to Beyond the Sword.

As far as I know, there isn't. You should just learn to ignore it completely, no other way apart from moding.

A fairly extensive list can be found here.

You do not need any mod to do that, you just need to start a custom game: You can then select the number of opponents, their leader and civilisation and setup teams, among many other options.

I don't believe there is such a thing. The reason is probably that it's not just a convenience function - having such an order is a tactical advantage. In plenty of cases a weaker unit can move beyond visual range of a stronger enemy unit, forcing the stronger unit to guess which way it has gone if it wants to catch up and attack it. This is particularly true at sea, or when the weaker unit is in its own territory on a road, or is an explorer. If a 'follow' command existed then this would change the gameplay, preventing the weaker unit from escaping.

You cannot found a corporation while the "State Property" civic is active. I have used freehand circles below to indicate the nature of the problem.

For mods in general, be sure your currently installed version of Civilization is compatible with the mod. In this specific case, the Caveman2Cosmos mod did not work because Civilization IV: Beyond the Sword was not patched to the latest Beyond the Sword version, 3.19. The in-game patching has not worked for me on the three computers I've tried with it, but fortunately it is also possible to manually download and install the v3.19 patch from the downloads section of Firaxis Games' website. This worked like a breeze and I am now able to play the awesome C2C mod.