The old "txtadv+world.rkt" module is now split into two parts: "txtadv.rkt" and "world.rkt". Aside from the split and necessary `provide' and `require' declarations, the only change to engine and world descriptions is the `start-game' call at the end of "world.rkt", which passes to the game engine all of the declarations that it formerly used directly. To play the game, run the "world.rkt" module.