You haven't filled in all the required options in your unrealircd.conf. All of them are within the set-block. Please check the documentation for the proper configeration
Unless you're planning to link a server to the network then you really are better off using a stock version of unrealircd. You're going to run into a lot of problems trying to run our modified version as a standalone ircd.
Nevertheless as for the errors, you just need to add them to the set block with their appropriate values. server-list-url is the message sent to users when they use the /map command, hidden-server-name and hidden-server-description are fairly self explantory - for example on the network they'd be set to "*.swiftirc.net" and "swiftirc network" respectively. The killer-string is what should replace the servername in kill messages (it's also set to *.swiftirc.net).
All of those configuration options are part of the server hiding update we made a few months ago.
Again, you should really be using an unedited stock version of unreal instead of ours.