I'm guessing you tried this immediately after getting it? As with custom items, custom NPCs will be put in your inventory immediately after clicking the button. However it will not spawn at your location until the NPC team take a look and accept it in. At that point it will have a location.
Also, what do you mean tags for conversation? DO you mean that inventory tags for organising stuff? Or something else?
Location wil be the room where you submitted it (or possibly where you are now - not entirely sure on that).
As for the tags for customs, you are possibly looking at old rules for custom speech trees. At the moment all NPC speech as been disabled, including custom NPCs. There will be a Sim News announcment once they are back, and custom scripting can be done again.