Well, I suppose that it's possible that your hosting provider is limiting the sort of files that you can upload to your dedicated server, but it'd be the first time I've ever seen a TOS like that, and I've been in the business a while.
If your server is managed, I'd definitely contact them to see if they can help you get those files uploaded. If it's an unmanaged server, then I'd try to upload the files to a different location on the server and the see about moving them where they need to be.
EzRemake is right that you probably want to go over your firewall settings and make sure that the requisite ports are open. NWN requires UDP only and the ports that need to be open are:
- Ports 5120 through 5300
- Port 6500
- Port 6667
- Port 27900
- Port 28900
Out of those, only the first range (5120-5300) are actually used by the game, and even then I'm not sure you need the full range, but you may as well open them all. Also, check with your provider to make sure that they don't have a firewall blocking those ports further up the food chain.
Out of curiosity, what version of Windows is running on your dedicated server?
Akin