You host it by running it.. it's hosted on your PC.
Buildings setup:
http://theuniversal.net/forum/viewtopic.php?t=1162. They're all just sat there in the forum, you know :)
However.. maybe you need micro-advice. Basically the characteristics of buildings on each world are stored in a file called buildings.dat, which lives in your world server's /data folder.
That file is created and edited using the program BuildingsData.exe (the bdat editor), which lives in your universal root folder.
Run the program. Go to the file menu, select "New". Then click the big "Add building" button. Congratulations, you've added a building (etc). You'll see it appear with some default settings.
Double-click that building entry to access the specific characteristics of that building. You probably won't understand half of that screen - I certainly don't - but by changing the various values there you can change how the building behaves, what it's called, and so on. If you want to build a good economy world, you'll spend a lot of time here working out which buildings sell what, how often they produce things, etc etc.
When you're happy with that particular building, click "Ok". To add another, click "add building". Repeat until bored and/or finished.
Then save the bdat file (File/Save As) in your world's /data folder.
Then, if you run your world server, and go to the Tools/Buildings Editor menu, you'll see the list of building types you've just set up in the bdat. Then you can assign models and textures to them.
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