There are a huge number of mods for Civ V on the Steam workshop, and it is simply not practical for me to play test games myself with every possible combination. Please help me (and your fellow players) out by posting in this thread when you discover an incompatability between Age Of Coal And Iron and another mod.

FAQ
Q: What types of mod is Coal And Iron likely to be incompatable with?
A: The mods most likely to cause problems are ones that alter the tech tree by adding or moving around technologies, especially if those changes are in the Industrial Era. Mods that alter the science victory will also conflict.

Q: Does Age Of Coal And Iron work with mod X?
A: You can find out yourself by starting a game using both mods. Let your fellow players know the answer by posting here.

Q: I've started a game using both mods, how can I tell if they're working?
A: If the game is playable, and the features mentioned in both mod's descriptions are present, then the mods are compatable. If the game freezes, crashes to desktop, or content that should be present is not, then the mods are not compatable.

Q: I'm playing with lots of mods at once, how can I tell which one of them is causing the problem?
A: Disable one of the mods you wre using and start a new game. Keep disabling mods one at a time until the game works properly, the one you just disabled is the one causing the problem.