What do the import/export data functions do?

Another question: How do I remove a dependency on tribunal?

Import/Export lots of info at once. I've never use the function, so I don't know exactly how it works.
It's not needed for normal modding purposes.

You can remove dependency with TESDTK (http://www.tamriel-rebuilt.org/?p=modding_data/utils)
There a few other tools that can do it also, like EE or Wrye Mash. But TESDTK is what I've used.

import export will take and list info to a text file (export) or load that same info into the game (import)

What info, you ask? All of the reference items, GMSTs, birthsigns, pretty much everything that isn't an instance item. (If you are unsure of reference item versus instance item: you make a box it is a reference item, then you put that box in a room the box in the room is an instance item of the original reference item box)

If you export data its harmless, try it and see... it just makes a text file you can look at. Import if you do it can change things in game, so keep that in mind.

ST