Hi Juha,
Thank you for your contribution. Indeed, depending on the network devices used and their settings, broadcasting may be blocked.
However, another consideration is that CueCore3 does not, at this point in time, allow for direct throughput from one Art-Net universe to another. When that universe is the 5th or higher. So to record the scene while viewing the content on your RdmNode or SpiNode, set the node to the same Art-Net universe(s) that the CueCore is receiving, and output to for instance your subnet broadcast address (192.168.1.255, for instance).
We realise that this is an inconvenience, and are working on a solution for it.
Have a good weekend!