Oh well, guess I'll have to increase the <iThreshold> values in CIV4CultureLevelInfo to make it playable then.
How is it NOT playable?
Just use higher difficulties, if you think this is "too easy" and thus overflows too much, and that's it.
It has absolute zero effect on the factual gameplay anyways, duh.
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Waaait a sec.
Does it also DESTROY the culture SPREAD on the MAP?
I had it once, but didn't pay too much attention to it.
Now, if THAT is the case - yeah, something must be done about it.
Probably REALLY the best solution is to add a Max Cap Level that is literally that - max cap achievable software-wise.
Then it would still have "where to grow", and thus wouldn't switch into negatives.
But it's not the numerical limitation that causes it, just that you are ABOVE your MAX Culture Level, so it changes the VECTOR downwards.
Make it unable to surpass that - and it's peachy.