In my current game I got the Dread Lords mega event again. Unlike all previous times, they spawned in a far off corner of the map. I didn't even find them until about twenty turns later, so they'd had time to build up a small fleet. In the hopes of nipping the problem in the bud I've moved the bulk of my defensive forces towards their far off homeworld. When I went to destroy the troop transport that was encroaching towards one of my allies, however, I was greeted with a warning that if I did this the Dread Lords would declare war on my empire.
Umm, aren't the Dread Lords supposed to be at war with everyone from the outset? I never negotiated with them, but we appear to have started out with peaceful relations. I've heard of an assortment of glitches with this very promising event, but not this one, so I figured I'd mention it.