Hi,
Good to see returning members.
There are several ways to get RT3 running on modern machines, the best is a thing called dgVoodoo2 that Private Codex
shared. Search that on Google to find the download page. Simple instructions below:
The download site has a couple links to documentation first. Just look for the one called "dgVoodoo v2.54"
When opening the zip you will have some readmes, dgVoodooCpl, and two folders.
Place dgVoodooCpl on your desktop.
Run this.
Under DirectX settings, make sure to set VRAM to 1024MB (this is analogous to the texture fix). Can turn the watermark off too. Can "Force vSync" to stabilize frame rates.
Now go into the MS folder of the zip.
Select D3D8.dll
Place that in your game folder
Run the game
Go to graphics settings and make sure the "Disable Hardware T&L" switch is off.
Restart the game if you changed that switch.
You're done.
If you got the game from GoG, there is a little extra step needed for that version of the executable.
Long version. Short version:
Remove/backup the file d8tx.dll from your game folder.
Rename the file D3D8.dll that you just put there with the name "d8tx.dll"
The game will now use the dgVoodoo instructions, enjoy.
A fair bit more is understood about the game now. Gumboots especially has been instrumental in this. There is a script to import models from Blender now. I will let him explain the details of that. It was his doing, and he has made a nice handful or two of new engines.
At present sbaros is the most active in the game I think. But, a few years back, Gumboots and I investigated in depth the fuel cost, engine lifetime, breakdown, etc. principles used and calculated the formulas for many things. He reverse engineered the more difficult formula for performance. We made several spreadsheets that cover every criteria. Something interesting: the car weights from the in-game display don't match what is in the file, so the game misled us all this time.
Other details were also discovered, for example: when you start the game and then start a scenario, the random generation is actually broken. There are only 2 possibile seeding patterns. In order to make randomization work you need to exit from the first load to the main menu and do another. The "first load" doesn't need to be the same map. You can even load a saved game first, and then go back to the Main Menu and start a scenario. There was some old information that indicated that reloading a map might cause more resoruces to spawn, but I believe this is not the case (boring particulars of some tests
here).
Lately, there are few new maps, Gumboots has reworked a couple to high standard: sattelite shots for the painting, accurate projection, good story, custom engines, etc.. A few years back Oilcan made a good number of maps. I really enjoy the economic style of his maps.
That isn't all. I can go into more details for the topic of your choice. Other than modding, who I am not qualified to talk about, what aspect are you most interested in?
I recall coming here for all my RRT3 needs. I did try to re-visit RRT3 a few years ago...I got it to install, but I could not get it to play. Currently I do have Railroad Empire and Transport Fever which is a fair substitute for RRT3, but doesn't have the same charm.
You can't simply move the updated RRT3 icon into the RTT3 folder. This will create a .url file or a shortcut icon. This never works. You actually need to copy and paste the updated RRT3 .exe file into the RRT3 Folder for it to stay an .exe file! I new actually remember having that same problem long ago. All is working now.
I'm only 70 but I sure do feel a lot older. I wish I knew back then what I know now. Id'a taken better care of myself. 
