MegunoLink

For example, if no incoming data received within the last x seconds then throw up a warning dialog or provide some other indication to indicate that the displayed information may not reflect the current situation.

My main concern is having an interface panel that displays old information due to loss of comms and user is unaware that this is the case.

You could have an indicator which flashes on and off to indicate that the comms are running and the numbers should be up to date.