Hi, you can have multiple cnMaestro On Prem instances connected to the same Anchor account so no need to create a new Anchor account. I recommend you create a Cambium Support ticket to get the assistance you need to migrate the data from the old to new On Prem accounts.
In the web admin of my old cnMaestro on-premises installation, I disabled the Anchour account to avoid any errors and then configured the Anchour account in the new cnMaestro installation.
Then I downloaded the backup of the old cnMaestro and uploaded it to the new cnMaestro, and everything went well.
cnMaestro was working on Proxmox.
However, after a week, we had to restart Proxmox, and unfortunately, it stopped working. Using .ova files in Proxmox is unreliable, so we had to reactivate the old cnMaestro on-premises installation, which has been running on VirtualBox for years.