Is there a way to reverse a train in Sid Meier's Railroads? I'm in the tutorial and the 2 trains are stuck on the same line. I try to edit the routes, but the game will not let me change anything.

I remember having that problem when I played this a while back. I don't think you can have two trains on the same track. You may have to uninstall everything or find the save file and delete it, in order to restart.

Not if you're describing the same problem that I had. I was only in the tutorial when it happened, I believe. So I didn't have a great loss. I just made sure that I never did it again. Maybe someone else has a better solution that I'm not aware of.

It's just really strange to have a train game with no means of reversing the actual trains. Even in real life, trains have to go backward sometimes! :P

I agree. I'm surprised the developer didn't see this or think of this when making the game. The way the game plays, I guess it just wasn't intended.

Also, have you ever encountered the animation bug by any chance? Basically the wheels and the running gear of the trains will all-of-a-sudden stop working and I can't figure out why.

Can not say I have noticed that.

It looks like the bug occurs when a lot of switches and crossings are used on the tracks. Have you tried that?

See if it happens with the 2-6-0 Mogul engine.

This can be done, but requires some manipulation of the train's route. This game is setup so that if a train loses its current destination it will proceed to the second stop on the list. This can be used to reverse a train.

If that sounds a bit complicated, here's how to implement this: Edit the stuck train's route so that it only has two stops with the second being the one you wish it to go to next. That would be the one in the opposite direction to what the train is facing now.

EXAMPLES:
If the train only has two stops and is currently headed to the second stop, delete the first stop and add it back which will automatically make it the second stop and the train will turn.

If the train only has two stops and is currently headed to the first stop, we need an extra step. Delete the first stop. Add it back. Exit the routing screen. But, the train didn't turn yet. To make the train turn, re-enter the routing screen, delete the first stop again and then add it back making it the second stop. Now the train will turn.

TIP:
Trains tend to jump signals in stations. Designing track to avoid this can prevent most jams. Make any split of one track into two far enough from the stations that the rear of any train in the station is still on the single track section. Make sure that any signal other than those near a station provide two options for a train. Passing siding or Y-branch. If one is careful how he uses signals the game can be run with little more than the occasional jam.

Is there any way to manually add a train signal? Also, how does one set player one to be the color red? It always wants to default to blue for some reason.

Most reliable trick to make signals is to select single track build and the location you want the signal as the start of that build track section. Lay a very short section of track at a sharp angle to your line. The shorter the better. The idea of the sharp angle is to make selecting the track easy as we we then immediately remove it. This refunds almost all the build money and leaves a single-choice signal.

Another trick is to place the track build cursor back right on top of the start point. It must be a $0 build. This works, but tends to leave little stubs that aren't visible. These stubs can be a pain if removing that track or signal is desired later in the game.

Removing signals requires that the track on one side of the signal be removed and then the line rebuilt. In order to remove the track no trains can be using it as the sole route to their destination. This often means changing train rosters. So better to think carefully where you put them in the first place.

Sorry, I don't know how to change the player color to red.

This game is so buggy it should never have been released. But it's also a lot of fun to play.
A few hints:
1. You will need to build a lot of double tracks that join into a single track for each of the lines you have running through your stations. Sometimes, you'll even need triple lines.
The absolute minimum sized piece of track you can build costs $0; but the minimum sized piece of track a train can run on costs $2,000. Each cargo car or passenger car uses up a $4,000 length piece of track, and train engines can use anywhere from a $4,000 piece of track to a $7,000 piece of track. Since the smallest piece of track usable is $2,000, that is what I'm referring to when I say a 'section'.
A. Depending upon how late into history you are playing, some of your more modern engines will take up 3 1/2 sections of track. Some train engineers don't stop at the signal light, but half to a full engine length beyond the signal. That means you may need to place your connecting track from a double track at least 4 sections away from your stations signals. In many cases this is impossible, and then you'll have to improvise.
B. In order for a train to go around another and get onto a single track or a double track, it needs its full length. In other words, if your train has 8 cars (2 sections each) plus an engine of 3 1/2 sections in length, it needs 19 1/2 track sections of open space to move into. Some cities signals are only 9 track sections apart and that means a long train that is sharing a double track with another train will never move. (In France, you will either need to create tracks with extreme zigzag type curves, build in an A-C-B order, or build really short trains. See Exploit's 1 & 2 below for a way to partially ease, or even eliminate, the situation.)
2. Although only a Terminal is supposed to support 4 lines, in some scenarios even a Depot will support 4 lines.
3. Glitch/Bug... When playing the Pacific Northwest, always make sure Boise either has a Newspaper, or space to build one. Sometimes all the spaces for industries in Boise are used up by other industries and that means the scenario is unwinnable.
4. A connection is a connection. You don't have to run trains on a connection nor do you need to run passengers/goods unless the winning conditions demand it. Likewise, just because a scenario tells you to build an industry, that doesn't mean you have to ship what that industry needs to that city. (Refineries and Power Plants both use oil but refineries make goods you can sell and power plants turn those potential profits into smoke.)
5. Be careful laying track. Even though you see the words 'even grade', or 'moderate grade', when you build track the track is laid with the top of the rails being placed flush with the terrain. So you're really digging a hole. You cannot fill a hole once you've dug it and if you wanted your heavy cargo to go downhill, it might have to climb out of a hole you've dug. Also, the longer the track, the deeper the hole, so it's always better to build tracks in lengths that are less than $32,000 long.
6. Exploit 1... You can move a station sideways as far away from its starting point as you want; and even change the direction the tracks face provided you are willing to spend the money on track.
First Example: Using the double track feature build three $5,000 pieces of track beside your original track. Delete the three pieces of track closest to, or furthest away from, your stations loading area. Quick save and quick load, and the station's new loading area will align with the only piece of track you have left. Repeat this 10 times if you want to and your station will keep moving sideways. (You can often get away with using $0 pieces of track, a second to last long piece, and then doubling beside the long piece. Experiment!)
Second Example: Build the shortest piece of track possible that heads the direction you want, and which is still within the loading area of your station. Add a $5,000 extension. Delete the curved piece of track, leaving the $5,000 extension. Use the Double track feature beside your $5,000 piece of track and so long as it is still within the loading area of the station it will turn solid grey indicating it is part of the stations loading zone. This can be especially useful if a city or a resource is at a terrible angle to the direction your original track faces. Also, you can actually fit 7 pieces of track within a stations influence. The station will only use 4 of them but trains that are not actually stopping at the station will 'sometimes' use the bypass instead.
7. Exploit Two: A Free Terrain Editor
Build a piece of track but don't actually release the mouse button to place it. Do a quick save and then a quick load. Even though you didn't build any track, the line where it would have been will be permanently etched into the map. You can cut a trench through a mountain, pave over oceans or lakes, and even make underpasses beneath track you or your opponents have already laid. (Since I never need to build tunnels, and only build bridges when absolutely necessary, I try to get my opponents to bid really high for those abilities when they come up for auction.)
I use this exploit to build railway lines that are just above sea level when I can. The actual city my station is at may be over 1,000 feet above my station, but my trains never have to fight their way uphill to get there. Also, it almost always guarantees that whatever heavy raw resources I'm shipping to town must go downhill. If I can't build sea level track, this exploit also allows you to build raised track to cities that are lower than your starting city. Building 'raised' track is also how you pave over water.
*Note: Because building a track digs a hole, you should always start your new 'editor' track on top of track which is at least three pieces of track (or more) behind the last piece of track you've already built.
8. Not always, but sometimes you will need to build a new train while another train is in the station, or stopped at another station, so that the new train doesn't build on the wrong track.
9. Finally, despite your best efforts, some train engineers are impatient and will always creep one half to a full engine length beyond where they are supposed to stop. Sometimes building a small connecting track to allow blocked trains to pass will be enough, but sometimes you'll just have to delete the offending train and hope the next train you build will have a better engineer.

I bought, but haven't played, GOG's version of this game yet. The regular game crashes often and even more often if you haven't used 3GB Enabler or similar software to overcome some software's 3GB memory barrier.
Also, because this game has memory problems, late in the game a saved game may have more information than the game can process and loading a game won't prevent the game from crashing almost immediately. When that happens, you need to load an earlier save and hope for the best. (Sometimes just quitting the game and re-starting it is sufficient.)