We did change the Maelstrom to reverse the wind/sail direction in almost all cases. The problem became that some ship mast models were developed with this problem in mind and the modeler inverted the geometry with a -1 to account for it; those models rendered correct sail vs. wind direction in the original engine, but when we reversed the calculation, now they are wrong. Also, some of the models were changed by modders (see the PA! threads) where they duped the masts, made the original mast invisible; these models now also go backward after we reversed the calculation. So leaving the calculations has some models correct (if the modeler reversed the geometry setting, or they where "fixed" by modders), and some incorrect, but when we reversed, now the behavior is swapped where the previous correct models are now incorrect, and the previous incorrect models are now correct. The only way to fix is to change the incorrect models because we can't determine what mast/sails were already "fixed" or not. We made it relatively easy by just adding a miscellaneous locator label in the specific mast that is going backward:
Just use TOOL, find the relevant _rey mast model, add a locator named: useOldTurn
If that label "useOldTurn" exists in a mast model, that mast will perform opposite to the wind that you see currently in the game. The other trick is to change the XX from 1 to -1 or -1 to 1, but that will change the actual geometry when reading the file and the normals will probably be reversed, so the lighting effect on that mast might be wrong.