I am curious as to which folders one would have to alter to say change the Marius Event so that it always kicks in at 240BC, that is altering the date of an already existing event. How would one change the files to make the Marius event kick in at this date?

Also would it be possible to create new events such as earthquakes, plagues etc.

I've looked but things are a bit over the place and I could find no thread directly dealing with this question and the forum search function is next to useless.

The former question is the more important here though. Any help would certainly be appreciated.