Also, I found the bug that caused Orthodoxy to spread all over Western Europe. In short, I tried to implement a rule where Catholicism could spread like Protestantism in all areas where Protestantism spreads more easily than Catholicism, before Protestantism is founded (Orthodoxy gets the same deal with Catholicism before the schism), but accidentally gave the benefit to Orthodoxy instead. Still testing the fix but it should be up soon.
(I implemented this in this branch for no good reason, but since I'll merge soon anyways that doesn't matter much.)