No, I don't think Oppie's program was what I was thinking of, although that would not be bad. I was thinking of a program that would automatically cycle through train sets as the game ran so that different varieties of these train sets could be used. A train set would be composed of the plugins for any number of engines and their matching cars. For example, an Amtrack set may have 3 amtrak engines and a dozen amtrak cars, and a TGV set would have an engine or 2 and sevral different orange cars. These train sets would be loaded into the plugins directory simply by moving certain files in and out of it. This program would create the illusion that only one type of train was being used at a time. but then again, if Oppie's mod had an option to select random train set im sure it would be the same