It doesn’t require access to the external network, but may require LAN access if you’re trying to play to a networked endpoint.
No.
Whatever’s causing your problem is most likely nothing to do with what’s logged (comprehensive or otherwise), nor when it’s logged. That said, I have no further suggestions other than to repeat that it would be helpful if you could post more comprehensive details about your entire system (networking gear/topology, endpoints and so on). In the absence of this information you’re not giving us (or support) much to go on.