@olivierlambert
Thanks!
Looks like the guys at CS have not really tested or maybe do not have the resources to test CS with all the hypervisors. The fact that XCP 8.2.1 or 8.3 is not listed here may mean that it is not yet tested.
https://docs.cloudstack.apache.org/en/4.20.0.0/releasenotes/compat.html#supported-hypervisor-versions.
XCP 8.2 is near EOL, 8.3 LTS is almost out and, CS 4.21 is out in August 2025 so I'll wait and see.

No luck for me trying out CS and XCP-ng in May 2025. I cannot add any hosts.
Still stuck here even after redeploying CS and blowing away the XCP hosts.
"Cannot transit agent status with event AgentDisconnected for host 8, management server id is 206863096530162,Unable to transition to a new state from Creating via AgentDisconnected"
XCP 8.2.1
CS 4.20.0.0