Anyway, I didn't even notice the light sides on the mountains should have actually been the darker sides (if I keep the other shadows like they are). But you are right!
The mountains/hills are something I slapped together by using some several bevels and blurs. There's no real shadow effects in there, so there isn't a "Use Global Sun Direction" for them, unfortunately. If I want to fix them I have to edit the other shadows. Which is no problem, but rendering the map again will take about 1.5 hours work of cutting and pasting screenshots and *that* I refuse to do for now