#2: Colonization range is much shorter compared to vanilla even in the mid 1500s, with diplo tech in the mid 20s, Spain cannot colonize any province in today's Mexico if it does not have a foothold in the Caribbeans. #1: M&T only allows for 10~20 settler increases per year, making colonization painfully slow.
I just tried the Meiou & Taxes mod for the first time - gorgeous mod, really fun, but the mod has a problem with AI Spain/Portugal not being able to conquer/colonize the New World.
Sorry for the provocative title - just angling for more views & opinions really.