50. US_03C + Horseman doesn't upgrade to anything. I can still build it.
Well be corrected
51. I strongly recommend you get rid of the US_01S # Settler when the Americans can build the US_06S # Settler. The only benefit of the older settler is the cheaper cost. Otherwise, the new one is vastly superior.
It's there for "roleplaying", if you want to play a little longer as the natives resisting the invasion of the evil white colonist
52. Church (with the capital C) no longer provides culture after it becomes obsolete. They are still in my cities that built them. However, they still produce the two content faces. I'm glad for that, because if they didn't, I'd have to rebuild the church in every city. I think you should rename church to something like Chapel, or just something different.
Damned! It was supposed to disappear, so you'll lose the happy faces to simulate the turmoils of the reformation.
Perhaps it would work if I remove the culture bonus?
53. When I fortify the US_06S # Settler, the graphic grows almost impercetibly during its animation.
Nothing I can do here, it's just borrowed graphics
54. The Cathedral looks really weird. I can build the cathedral in my cities, but I could never build Cathedrals. cathedral uses the Cathedral civilopedia entry.
They both use the same civilopedia entry (same as bastion and walls). I don't know why you couldn't built Cathedrals. I'll have a check this evening. Normally you only need a Church.
55. I just build an embassy in Rome and they are doing PITIFULLY. They have NO buildings in Rome. The year is 465 AD right now.
No building?? What are they building then?
57. Pollution due to population is skyrocketing in New York. It has a pop of 20 now.
58. Pollution is really bad now and I have no way to clean it up.
Did you build the sewer and/or large sewer?
To get to this population size, you'd need major port or multiple stories housing. What is your tech level?
59. Why would a Newspaper produce an unhappy face?
Oh no! There was a flooding there! Look, the government will increase taxes!
Read the civpedia description, I think I explained it.
60. Stock Exchange has no civilopedia text.
I may have forgotten this one.
61. The pollution is now causing starvation.
Perhaps I should allow to clean pollution earler?
62. Shouldn't the US_07N + Merchantman render the US_06N # Caravel obsolete?
The caravel is in the "combat line", and will become obsolete with frigate, the merchantman is a transport
64. I got a notification that Britain declared war on the Greeks. (Wrong civilization names.)
I'll look into it
65. Right clicking on Garrison gives me the civilopedia entry for Barracks.
Same civpedia sharing as bastion and walls
66. My obsolete Barracks remain in my cities, eating up maintenance costs. I wonder how the AI handles this.
It seems to confirm that buildings with culture are not deleted when obsolete. I will either need to remove the culture contribution, or stop using so many obsolete buildings
67. I noticed that I can build US_06I + Musket, US_07I + Musketeer, US_05C + Mounted Warrior, and US_06C + Mounted Shooter all simultaneously. With the 2 speed of US_07I + Musketeer and its fabulous numbers, I don't see any point in building the others.
Same as before, you keep them if you want to play native a little longer, they are kept mostly for flavour.
68. I just got Piracy and I can build a 7I - Naval Infantry. What's this? It has no civilopedia description. Its numbers are through the roof though. 7I - Naval Infantry has no icon either.
69. Naval Infantry are so powerful why would I build anything else?
An old unit that shouldn't be available.
70. There are two specialists that produce money and both are available at the same time. Seems wrong. One produces 1 coin and the other produces 2
I'll check
71. The icon for the 06N - Privateer looks like a green transport ship, and I can build it at the same time as the US_06N # Privateer.
The 06N - Privateer shouldn't be there.
73. 7I - Naval Infantry are awesome. A 15 attack and amphibious assault.
Stop cheating: If the name doesn't start by US_, then it's an artefact from a previous version of the game and you should not have it

.
Rule: if you play as US, you should be able to build only US_ unit (except for the starting unit, generated leaders, etc).
If you see something else, then it's an error.