Hmm... as far as currencies... Due to the tensions/war of the first (Loren) game's era, it's unlikely that the Elf kingdom and Empire use the same coinage. They are probably making inroads to that, diplomatically speaking since they've had 10 years of relative peace. But they're both proud peoples so I'd guess the going is pretty slow. Zoltar obviously would use different currency from either place.
That said, gold is shiny and generally considered nice so the term "gold coin" is probably a good catch all for money wherever you are. If there's time, there may be a scene about converting empire gold to elven gold.
My guess is that the Amazons would use empire coin. Internally, they're close knit enough that I can see a barter system seeing common use. Especially since the Amazons prize physical prowess over material wealth. Since the empire is more willing to trade than it seems the elves were, any coin the amazons kept would have been used for trading with the empire. So there was probably already an inroad there, and when the borders opened up after the first game, it would have been an easy policy to just adopt that coinage, again, for trading purposes.
Somewhere there's another game about the geopolitical ramifications of all these world-ending events, but I don't think that's going to be in this one
back to measurements for a moment: I think I'll do a mix of medieval and metric. So, a "pace" is the base unit of distance. Then it's a tenpace, a hundredpace, etc, etc. Metric is just easier on the math.