I’m quite new to zwave things.
I’ve build a network with around 30 devices.
As I encounter some communication problems, I had a close look to the “zwave” log. When the software starts, I can find that the controller asks each node for its routing table (who are your neighbours ?).
So I build a little exhaustive sheet with the results and I can see that the table is completely mad. It needs to be recalculated.
If you have the latest version installed of the zwave service, (see software update inside administration panel), then inside the controller commands there is a button to rediscover the neighbours of your devices.