Sorry, I should have made it clear I was using network-mounts, not DLNA. I thought I had by listing foxlink in the installed packages, but I can see now that doesn't tell you anything!
I initially tried the standard DLNA client-server approach. The problem with it is the FF/RWD functionality is virtually useless/unusable, and features such as delete/move recording aren't available. Another significant omission is the ability to pause the playback in one room and continue from the same point in another room.
Unless DLNA with the CF offers these features, then I can't see the point of trialling it even as, even if it does work, we'll never use it. Will testing it tell us anything about the overall installation? If so, I'll happily give it a go.
However, now I know not many folk have tried running network mounts in both directions, I will trial running that in one direction only - we could live with that limitation if it turns out to be necessary.
Does anyone successfully run network mounts in both directions, using either foxlink or network-auto mount?