Take the effect.mes file and put it in the C:\Sierra\Arcanum\data\rules folder. In case you installed to the default directory and there is no rules folder in the data folder, just create it as a subfolder in the data folder. In case you installed the game to another place, do the same at the appropriate place. 
Take the backgrnd.mes file and put it in the C:\Sierra\Arcanum\data\rules folder. In case you installed to the default directory and there is no rules folder in the data folder, just create it as a subfolder in the data folder. In case you installed the game to another place, do the same at the appropriate place. 
Take the gameback.mes  file and save it in the C:\Sierra\Arcanum\data\mes folder. In case you installed to the default directory and there is no mes folder, just create it as a subfolder in the data folder. In case you installed the game to another place, do the same at the appropriate place That is all.
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