This is a set of suggestions intended primarily to facilitate short-term movement of goods over a consistant path.
The rail line itself would consist of a set of tracks built from iron bars, treated wood (Hard, rotproof, would be most appropriate), and some ammount of clinker to create a level railbed. It would be subject to slope restrictions, similar to what was used in T1 for the block pushers. Turning capability would be limited (using 8 points per coordinate, no more than 45 degrees / 1 step per coordinate). At either end of the line a cart could be attached / removed from the track.
Ore carts could be used on the tracks as-is, and would really only benefit to the extent that you don't accidentally push the cart in the wrong direction (perhaps making it irretrievable).
A second type of cart, the baggage cart, could also be developed. Functionally a chest on wheels, it can only be moved when on the tracks (when removed, you get to specify one of the 7 remaining exit points to push it to, where it would sit until reattached). To move the baggage cart it is treated as part of your inventory, thus you cannot move it if the combined weight of what you carry and what is in the cart is too high. A cart naturally has a weight modifier of 1/2 - 1000 debens of material within the cart counts as 500 in the person's inventory. A cart can be upgraded with any of three gearboxes. A one-output gearbox results in the cart having a modifier of 1/3, a two-output is 1/4, and a three-output gearbox results in the cart having a modifier of 1/5. Note that these are removeable upgrades to teh cart, and as such it would not be possible to disassmeble the cart and try for a better gearbox erquirement (of course, the cart could be used without any, so it's not a total loss).
The main future tech advance related to this would include the switchbox - merge two lines together, and allow the selection of which gets used.