Quite possibly. However, I am not familiar with that mod's data (or even what it adds, as I don't use it), and since few may know where to find what might potentially be causing problems, I'd recommend asking the maker of the mod. He probably knows it best.
I don't think is what was doing it, seeing as without the modified humans it worked perfectly fine and I've used multiple entity files before. I will try it without the extra entity file if it keeps acting weird.
Wow, sounds bizarre. I've never managed to get them to do that (nor have I managed to get the race I'm currently playing around with to live in taiga forests, thanks to a lack of a TREE_CITY tag).
It is a kind of weird mod, they aren't really elves though, just use the creature as a base. The whole mod is kind of Egyptian flavoured, so it is mainly desert and one or two big rivers in the world I'm genning - making it necessary for all races to live in deserts/mountains.
EDIT:
EDIT2: And bam! Suddenly they start working with tree cities, could be that cities can't be built on desert squares. I'll try changing it back to cities, see if that is the case.
Wait, they stopped spawning again, even with tree cities. What is going on with these guys?
EDIT2: Tried copying and pasting the entities from entity_new.txt to entity_default.txt, then deleting entity_new.txt. Genning Now
EDIT3: No dice
EDIT4: Making them spawn on mountains, to see if its the biome doing it.
EDIT5: They spawn on mountains. Back to the desert folks...
EDIT6: They've decided to start working again with tree cities. That was weird