It seems to be in the right section now.
As far as I know I've never heard of Kazlauskus in Shadow World. But that doesn't means it/he/she doesn't exists there.
It took a lot of time for traces of Agonar ( his staff is somewhere in RM spell law ) to appear, so it might be the same...
Only Terry will be able to answer that.
As for killing important NPCs, well, most of Shadow World is vague enough that it allows people to develop their own part of the world. As far as I know, it is done that way on purpose... so killing NPC is not a problem, as it's part of the evolution of
your version of the world.