Hi all
I repeated the autodiscovery process and finally it goes fine.
Be aware that, before run the autodiscovery, as requested I manually added a couple of VMs into the monitored devices.
I solved manually adding, into the monitored devices,
also a router placed on one of the networks to be discovered.
After that the autodiscovery started to work properly.
I hope it can be helpful for someone.
Kind regards
I.