Hi Dave,
It's wired. Up until now I just assumed it might have been my internet connection. Thing is TCP retransmits should take care of any missing packets, so unless the connection hangs for a while, I'm not sure why CMSF would display the network paused message.
Looking at the TCP trace, there are regular packets flowing at the time (server->client) and the client is ACK'ing the packets, so it's not a problem with the transport layer.
Other than ACKs, the client last sent actual data 30 secs before the problem occurs. I'm not sure of CMSF expects keepalives at the application layer, but appears the client just stops sending application data even though both client and server are alive, and the TCP connection still established.