EDIT: I've downloaded it and all I can really say is that you've put in too many high poly meshes in one place, therefore creating over crowding and lag. The map itself is wonderfully set out, but I've uninstalled it, because there is just too much over crowding and lag for me =/ I fail.
It's an epic map and I wish you good luck.
-downloads-
Now I have an excuse to bring Fireclaw back!