Not the first one,,

But,, can't get this;
Everything seems to work otherwise,
remote control, etc,,, AND this PC is a remote/satelite server/WS
for another network ( over VPN )

No traffic is blocked in either direction,
both this PC and the central Zen-Server can "ping" each other,
they also have the same DNS and both are IN the DNS,
both are also present in a local "hosts"

So, remote control, satelite storage/replication,etc = OK
still, in ZAC "Unable to connect through IP Address or Host Name"

Also, worth mentioning;
No local firewall, no windows-firewall,etc,, on either side..