How difficult is it to add new locations to the game?

Say for example if i was able to get a new map for a home from the daz website.
--How would i get it to show up and would it even work?

--Also how difficult is it to just add a new piece of furniture and have it show up as a placeable without using the workshop?

--Is it possible to move vendors around and or change their races?
Example: change the armor vendor to an orc warrioress.

I also wouldn't mind looking into adding some more actions for furniture and such.