I have spent some more time looking at this issue. I think the best option is as per your suggestion - withhold Placement updates if LIVE is disabled. I will see if this can be done for the next release.In that case, is it possible to add a feature that pauses the updates to the Octane Placement node while rendering is paused?
Right now I've given up on working with complex scenes because the lag I experience while doing so makes it incredibly frustrating.
Paul