Does anyone know how the scores shown in the game's "Hall of Fame" are calculated? I'm currently going through the original Rage of Mages singleplayer campaign but I don't see a "score" shown anywhere in the game's statistics. Searching through the manual, I only found a one line reference to it defining it as "The list of players who have completed the game, scored most and shown best results".

That's it. No explanation of what's taken into account (difficulty maybe? time spent? gold collected? quests completed?), no formula, nothing.