By "In the Tamriel World Space", I mean Mods which are actually IN Tamriel (i.e., like the default Towns are meant to be towns of Cyrodill). "In a New World Space" means a Town elsewhere-- maybe on an island, or in another country, et cetera.
By "Open" I mean like the Open City Mods, where they exist in the Main World space, and can be entered without loading a separate worldspace; Closed is the opposite-- how the Vanilla Towns are.
Thanks for your answers