Tipping mine cars?

For my rct3 game, how do you put in the custom tipping mine cars on any track and where can I get the tipping mine car?

I cant get them to work!

i think you have to download the steel worx thingy

I can't get these to work either. What is the steel worx thing?

Steel works is kinda like a trainer that gives custom sceanary. Im not sure what it gives completely beause i have a brain and knew rct3 looked like crap so i never bought it but i think thats what it is if my memory serves correctly.