This may be unrelated to the OP, but TNServer.exe is crashing for me as well when entering q to exit.
Using TNet version 3.0.2
Line #568 in TNGameServer.cs:
An unhandled exception of type 'System.Threading.ThreadInterruptedException' occurred in TNServer.exe
Additional information: Thread was interrupted from a waiting state.
Another very small note: Line #490 in TNUPnP.cs needs to be commented out to build the server without the UnityEngine namespace.