Kira076

Maybe I'm not understanding how it works then - where are any of the provinces that are pink or yellow on the map? All of those are variants of green...

... I just not noticed the drop down in the bottom right. Pretty sure I'm dumb

Yep I'm dumb. It all seems to be working as intended.

I just noticed there's still an issue with religions - it is showing some religions as extinct even though they have corresponding colours/cells on the map... See screenshot 

It doesn't seem to have, no. However I hadn't made any custom changes yet to religions, so I went ahead and regenerated them and it seems to have fixed it....