I vassalized them around 1480 only for reconquest in Muscovy and it was their 3rd idea group so they couldn't have required tech. I realized they are colonizing in 1540, after that I checked the file 00_basic_ideas and couldn't find the line preventing them from taking this idea.
I can't find any evidence that subjects ever had a restriction on expansion ideas. They definitely didn't have such a restriction in recent versions(see for example the idea groups wiki page in its revision from before the 1.33 release). What often prevents subjects from taking it, is that they either need exploration ideas or be a colonial nation or border an uncolonized province(this part is also unchanged). The last one is the reason why Kazan can take it. And the base weight for the idea group is very low, so countries which don't have a positive modifier are unlikely to take it.
If you release a country, they use the historical_idea_groups from their file in the common/countries folder to determine the idea groups. AFAIK the AI preferences are then only used to push some groups to the end of the list. I think it has something to do with very low factors, but not all country information is know at that point and that's why exploration ideas are usually not pushed back despite the x0 for subjects.
So PUs without explo can be given single colonies in colonial regions in the hopes of them getting expansion?
Yes, but "hopes" is the right word, because the chances are not very high.
Is this a joke? multiplying something by 0 makes it 0 and a weight of 0 means that the idea group will never be chosen
As I said, the chances are very low. And hordes are normally not in the Western, Eastern or Muslim tech groups so they get another x0.1 modifier which makes the weight 0.048 which is lower than any other idea group except exploration, naval and maritime which probably have 0 weight for them. In some circumstances, trade, religious and humanist can also have 0 weight. The other ideas have at least a weight of 0.49 so the AI is at least 10 times as likely to choose each of them.
I can't reproduce this. The only change in the Castilian/Spanish missions is how you get the restoration of union CB on Portugal and the location of the mission which requires Portugal.
I don’t think they do, just played Castile game and PU Portugal’s Hispanola colony didn’t let me do the mission
Things need to be documented in patch notes or an official changelog, not the half-dozen different dev diaries that come out before a release.
Maybe you need to own the province with the church/workshop yourself, but for the count Portugal's West Indies sure counts.
I'm playing with no mods. I'm not completely sure that the Havana workshop requirement can be fulfilled by Portugal's colonial nation, but I have completed both Claim Hispaniola and found Havana missions using Portugal's colonial nation's provinces for the count.
next game (probably next patch at the rate the first one is going) i'm going to try giving the canary islands to Asturias, to see if they will colonize the ivory coast for me. Basic idea is at diplotech 7, ~third war with castile, transfer occupation of Canaries to Asturias. Second war with Mali/Jolof, transfer occupation of Traza to Asturias. Should be in range to colonize the Ivory coast then in time for their 4th national idea. They should be able to core it at diplotech 7, and they get a free colonist as their 4th idea. They should pull trade into iberia, which is nice.... it always makes me mad how after I put forth the effort to subdue all of asia, france/britain can conjure up 10% trade power in the ivory coast for a sweet 60 florin payoff.
