"Authentication Failed --- Application will now terminate" Means client did not receive timely response from game server. (There are two servers involved, lobby server and game server).
Client connects to lobby server first, then to game server.
Possible reasons why client can't connect to game server:
1. War client is not patched. War.exe client has to be patched to work with ror servers. Original live version will not work. (Ror patcher will try to patch it, but sometimes fails if file is read-only or already running)
2. Data.myp is corrupt, read-only, or older version. (Have someone send you copy of theirs.)
3. Firewall/ISP is blocking game server port (different from lobby server port 8048)
4. War install is not version 1.4.8 build 573
5. ISP is doing packet shaping (see
https://en.wikipedia.org/wiki/Traffic_shaping)