there are a few comments and threads on the topic, but it really needs to be dealt with.

sometimes it gets so bad I have to unflag my vampires from all work tasks or put them into torpor just to get the game unstuck from the constant stuttering and pauses. it normally happens around dusk/dawn/eclipses but as others have pointed out, not necessarily all the time.

it gets really really bad sometimes, but I love this mod and can't imagine playing without it anymore.