I missed an important point that was explained by Aiwendil. You can't redistribute the art (maps, models, textures, etc) and you also can't run a public server with that art.
About the things that are missing, I'll give you an example with swords :-D
Let's say that in game we have "The Sword of Cutting +1". This item is made of:
- looks - 3d model, textures (you have this)
- type definition - textual description of the sword, damage rate, speed rate, the fact that you can use it with your right hand, etc (I don't think you have this)
- instances - how many swords of this type are in game, and where (you don't have this)
However, as I said the database that you can download, has a few axes, maybe some swords too :-P, but those are created for testing purposes.