The concept is simple: Deliver packages quickly to various locations for cash and exp. You start out with close, simple jobs and move up to hard, cross-country ones. You can earn no more than 3000 coins CX-ing a game-day. There are two people who give out jobs: Lou, whos jobs are cheaper and have a longer delivery time, and Pembrook (1d of Lou) whos jobs pay more and have a short delivery time. The exp/gold ratio is the same for either person. I believe its something like 1.3/1.
Directions from Xroads: 2e, 1s, 1w.