Like you're trying to browse a "lua" subfolder that doesn't exist on your DC.
The forum thread and attached link to the kb article make no mention of any subfolders in the DC you create. If you want subfolders, you'll have to create these yourself.
As far as the LUA goes, you should just need to give it the IP, Port and Creds. As far as the clients go, they will only need the IP and Port with no subfolders (unlike the default DC auto-created on the LUA which goes http://luaaddress:7070/clu-prod). Once the LUA and DC are connected however, you can export the the address of the remote DC to a file which the client LiveUpdate can read anyway.