Works, but I need some help with age transition. I followed your description and set antiquity age to 1, but which value makes the next age accept the end-limit of antiquity? By the end I was at 6/6, but upon entering exploration age, it reverted to 4, so i was 6/4 with some trouble ahead.
I also don´t want to give the AI some free limit up to 6, so it would be nice to only allow the limit they previously reached in the age before.
No issues and mod loads and seems to work, so I guess you answered your own question.