Maybe a weird bug or maybe I've made a mistake somewhere, just downloaded Civ4 Complete from GOG, followed instructions for SVN version (r364). Played two games of 600+ turns on epic speed, but events aren't working at all, I did not get a single random event. I DID get the fixed event from walking into Letum Frigis, but that's it.
In case it matters, modules I have enabled:
AnimalLairs, Arachnophobia, BannorExpansion, BlackDuke, ChislevExpansion, Dural, Dwarves, DynRel, Fortifications, Frozen (though I did have the in game option to prevent them being summoned), ImportantLeaders, lizard-art, LjosalfarExpansion, MagisterAshes, MoreGoodies, MoreEvents, NewTraits, NodeYields, PPQ_Effects, PPQ-Flavor, PPQ_Navy, scion-healthcare, SidarWanes, WateringTheFlames
Unrelated to that, I think the lair result that spawns the Battlemage with channeling 3 and random magic circles is a little on the strong side, both games I had an AI get taken out by what appeared to be a battlemage with fire or earth elementals, very hard to push through that if they have any of the good t3 summons, and the battlemage himself is strength 6ish and has more promotions himself. Easily the worst powerful enemy I've seen from a lair by far.