Thanks, y'all, I appreciate the responses and opinions. Since I am in the process of upgrading, I need to ask some questions in the Hardware Forum; I go with towers and use multiple drives.
I've got some things transferred with no issue using CM; when the cdp exports from TRS19 into a folder, then gets imported into T:ANE, CM will indicate any missing kuids and can dl. (CM 101, huh.) So that is easier than trying to associate, as long as there's internet. I'm acquiring some of the wonderful signature routes and building a solid version of T:ANE.
Trainz is a continuum, or appears to me. Many forumites have long strings of versions in their sigs. TRS19 is really wonderful and worth aiming for, IMO. My current FCT runs through the summer.
You can purchase annual FCTs (recommended) because they always manage to run out just when you need them the most. Yes this program has that effect on people. A continuum is a good way to put it. Many people have been here since the program's inception back in 2001. Their forum join date is incorrect since that was reset in 2006 due to a forum "crash". I've been here since December 2003 myself and started with TRS2004 and later bought the 15-anniversary set of the older versions, but yeah many people have years of experience.
Importing CDPs into any version of Trainz, is a lot easier if you drag and drop the CDP into Content Manager. This ensures you are installing assets in the right place. Having two different versions of Content Manager, however, does get a bit confusing!
A tower is highly recommended due to the amount of heat generated by graphics intensive programs. You want plenty of fans and ventilation with more the better especially during the warmer months. Since you are just setting things up, we all recommend putting your data outside of the C:\Users\<profile>\App Data data structure. With T:ANE and up, you can specify where your data goes. I for example have TRS19 data on my E: drive and T:ANE data, for which I still use occasionally, on my F: drive.
As far as mixing databases, don't ever do that. You'll be in a world of hurt doing so because some things are the same, but a lot is different. I have shared the same database over a network for the same version of T:ANE between my laptop when I used it with only one copy of T:ANE being used at a time. It worked, but it was slow going due the limitations of the network speeds. It was convenient, however, sitting on my deck and Trainzing, but the sacrifice in speed wasn't worth it. There was also that chance of things hanging due to a network glitch.
You'll be presently surprised how resilient, overall, the program is as well as the array of hardware that the program can operate under. I happened to replace my video card a few years ago, if not longer now, with a GTX1080TI. I don't run it at full throttle and enjoy smooth performance overall on my very, very detailed tree-covered routes. (I admit being from the Northeast tends to make me want trees, trees, and more green!). The thing is this program is a lot different than a fixed "game" with a set of limited assets. You are going to find that some assets are going to perform better than others, that some routes are going to be too complex even for a Cray computer to handle. The good news is you can modify these routes, the ones you've downloaded mind you, to your heart's content. Remove as many trees as you want, add in as many other details as you want. You'll see what I mean here later on as you get more into the computer.
Speaking of a Cray killer... I downloaded a very nice-looking route. It look fabulous, but even with my decent processor and video card at the time I could net get anything more than a slideshow. I opened the route up in Surveyor and had a look around. There I found a gazillion grass splines overlaid on top of more grass splines. There were also grass splines where no one would ever see anything to begin with. I cloned the route and did some lawn mowing across the map. It took me a couple of hours, but in the end the frame rates doubled. Yes, they actually doubled after peeling back the layers of grass. Did we see anything different? Nope. The grass is just as thick as before only there's less of it. With the Turf-FX available today, I may remove the splines and replace them with that, and that route will look even better.