I've released the long awaited update. This one was a doozie to finish up, but the results should speak for themselves!
New features:
Fix for homozygosity not being added to characters whose parents were avuncularly related or cousins when a link was dead.
Homozygosity is now calculated using variables rather than traits.
Discrete traits still exist, and now give players an estimated (to 2.5%) rather than exact value of homozygosity.
Homozygosity gain has been reworked to be a lot more realistic.
Localisation tags added to events just in case.
Removed the negative trait mutation chance.
It is now possible for a character to be born with both the lunatic and inbred trait rather than one or the other.
Reduced heritability of lunatic/inbred traits for unrelated parents (from 50%/parent to 25% as in vanilla).
If a character is affected by an increase in homozygosity the odds of inheriting genetic traits increase as well, depending on how high homozygosity is.
-This means that if two cousins both have the "Strong" trait their children are much more likely to inherit it than if it were two unrelated parents instead.
-Purebreds always inherit any and all genetic traits that parents share (affects vanilla CK2 and HIP traits).
Characters must be subject to a homozygosity increase to gain the inbred/lunatic traits.
Purebred now only requires both of a character's parents to be at 50% homozygous. This trait is now achievable by the 4th generation at the earliest rather than the 5th.
Purebreds are now immune to mutation (ie they will not inherit traits that their parents don't have). Only checks vanilla CK2 and HIP traits for now.
More complicated fractional relationships (ie half-cousins, 3/4 siblings, etc) are now checked.
I strongly recommend starting a new game before playing with this update.