Research on the net, there are countless plans showing how many pieces of sectional track are needed for various layouts.

You drill out the broken off part and find some plastic rod of the same diameter to make a new one.  If you build plastic structure kits, the sprues that hold the kit parts before assembly are usually pretty good for that role. I've done that a couple of times And they haven't broken yet even with 35 and 40 car trains behind the engine.

Contact micro trains

This sounds like the lubrication in the gears is gummed up.  How long have you had that engine in storage?  Also, long-term storage allows all the electrical contact points to oxidize, and basically shut your engine down.  Enough power is getting through to run the lights and sound, but not enough to turn the motor.

1.  Thoroughly clean all the wheels and electrical contact points you can get to.
2.  Take your engine shell off and painstakingly, tooth by gear tooth, dig all of the old lubricant out of all the gears.  Apply fresh lubrication.  I bet you will find that the old stuff has turned into kryptonite.

I have a feeling that your engine will run like a champ after all of this.  if not, refer to the post above and check for loose wires under the engine shell.

I don't believe that this engine is in any way ready for a smoke unit installation.

However, allow me to tell you about smoke units in models, opinions coming not only from myself, but many other experienced modelers on this forum.

The smoke itself does not in anyway look realistic, the physics of smoke cannot be scaled down to HO scale. The smoke resembles more an output from a cigarette inside the engine rather than a real locomotive. 

The smoke generated carries a fair amount of oil along with it as it drifts through the air. It will settle on everything in the room over time, leaving a film that has to be cleaned. Of course, with a train that is rarely operated that won't matter much, but you need to know.

And lastly, it's just something else that can break and not work right.

The front end looks like a New York central engine, but I wonder if that is just a different façade put on the Santa Fe engine.  I'm not familiar enough with either one of them to state for certain, but that's a common practice among manufacturers, to slightly doctor one engine to sort of look like another prototype without much retooling if any.  Bachmann's Berkshire are a great example of this.

Search eBay "ho steam locomotive tender only."  Right now, I don't see the tender that goes with that locomotive, but there are dozens of tenders there which means that the one you want is certainly going to eventually appear there, just keep a lookout for it. The locomotive is called the New York Central Niagara, maybe that will help the search.

eBay has tenders available all the time

Safety film on the Missouri Pacific on the late 1940s.

My favorite Railroad, my favorite time period.  The railroads were perfect art form in those days.

Watch, and comment.  Several very interesting interesting things are seen that I'll discuss later.

https://youtu.be/8ZgoSfD0TVM?si=QkhBPpOeQkSP0Por

As far as I know, you can use the older steel alloy track with no problem. But, the problem is that steel rusts. I think the only place that would be a problem is high humidity Regions. I live in one so I don't use it.

Fasten your track with appropriate model railroad track screws available at any model railroad retailer, Google is your friend.  Drill holes At the end of each section that doesn't already have holes.

You can also fasten your track down with various glues or caulks but I've been sorry every time I've ever done that, something always goes wrong or I want to change something in the design.

They Will not bring the Shay or the climax back because there just isn't a train set it would work well with.

Resets and renaming addresses are functions of your DCC system and aren't properties contained in the turntable itself.  What system are you using?

It is always worth paying a professional to install your DCC/sound decoders.  No endless research, no backtracing each wire to find out what feeds what, no frying the decoder if you get something wrong, and no accidentally putting the soldering iron through the tender shell. 

You send the engine off, pay for the work, and get it back nearly perfect, meaning you'll almost certainly need to manipulate CVS to get things the way you want them.  Motor control can always be improved, different sounds such as Whistles can be selected, and sound volumes are always unbalanced at default.

Those Shays are beautiful and worth the money to buy the parts to get them running right, in my opinion. 

I doubt Bachmann ever brings them out again.  In recent years, they have leaned very heavily back towards the Toy Train Market, which is a lot more lucrative than the serious Model Railroad market, which is where the Shays live.  Shays were really intended primarily for logging and mining operations, which are not nearly as interesting to a child or a beginner as some mainline train that Goes Fast, when Shays really couldn't do more than about 15 miles an hour at best and that would be breakneck speed for them.

If the Bachmann Shay is ever reborn, I'm good for one, but I'm not going to get a used one and go through all the twitching it takes to get it running right.

The answer for that will be found in your owners manual for the DCC system itself.