I've tried it, it's a really good mod, but the reason there are so few people is another..The reason is the poor curiosity/intelligence of most of the people, because people go always on populars setting , now NW is popular so anyone leave it to try a new setting like IE or North and south .They use the same setting more times without interest in new without think that M&B power are mods.
Just look at Full Invasion i've seen people play with same faction (Lord of the rings against Orks for example or spartan vs persian) 3 hours without think at the other faction inside that mod.