Normally the sequence of round winds is East, South, West and North (ESWN). In Mah Jong tournaments sometimes the number of round winds is reduced, e.g., the East round may be omitted. The sequence may also vary, e.g., some players may want to play only East and North rounds.
Four Winds lets you specify any round wind sequence you wish using the wind letters E, S, W and N. E.g., to play a six round game omitting the East round wind, you would specify 6 in the # of rounds box and SWN in the Round wind sequence box. The sequence can be any combination of wind letters and its length can vary from 1 to 4 characters.
Related topics:
Using five sets
Number of rounds
Dead Wall
Specifying how discards are placed on board
Using extended discard information
Charleston
Pass deal after East's win