I don't know how to use a mod such as a navy mod that allows you to have carriers and battleships. Does anyone know how to use a mod? can can you use 4 mods at the same?

I do believe mods come with installation instructions.

And I'm not too familiar with modding, but I do know that modding alters the scripts and I'm fairly certain that there would be many conflicting scripts should multiple mods be installed at one time. Not to mention unit models would conflict as well. I would imagine the game would even crash.

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It depends from mod to mod, most mods will come with an installation files, some others won't. Same with merging mods together, is most cases the mods would create a conflict by using or editing the same file already present in the game, and thus would not work together without modifying them. There can be cases, however, that two mods would work fine alongside each other.

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You should just take a look in any help files or instructions supplied with a mod.

And the game would indeed crash most the time when you use more mods at the same time but there is a way to install more mods at the same time and have multiply shortcuts, each for every mod.

The game will crash most of the time with more mods installed is because when you mod the game you change some of the INI files in the game (the INI's in the mod overwrite the original ones) and when 2 mods overwrite the same file only 1 of the 2 INI's will be used. This can result in missing or invalid scripts.

For running mods alongside of each other, there are multiply topics explaining how to do that.

But installing a mod is worth the trouble because good mods really make the game more fun
(I recommend Generals Shockwave, it comes with an (un)installer and a launcher so you can also play the original game)

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