WireGuard Setup with a failure

[hansdampf]

Hi,
i set up wireguard the way its described at the online-help: https://docs.opnsense.org/manual/how-tos/wireguard-client.html.
But at the end i got errors when creatíng the gateway and restarting WireGuard:

/usr/local/opnsense/scripts/Wireguard/wg-service-control.php: ROUTING: not a valid interface gateway address: ''
/usr/local/opnsense/scripts/Wireguard/wg-service-control.php: plugins_configure monitor (,WG_GW)
/usr/local/opnsense/scripts/Wireguard/wg-service-control.php: plugins_configure monitor (execute task : dpinger_configure_do(,WG_GW))
/usr/local/opnsense/scripts/Wireguard/wg-service-control.php: Skipping gateway WG_GW due to empty 'gateway' property.

I have set up an OpenVPN-Instance exactly the same way regarding interface, gateway, rules, port-forwarding...
and it works out of the box like a charm. (Gateway dynamic)

Only WireGuard doesnt. I didnt get any traffic passing the tunnel.
So finally i got it working with adding the tunnel-IP xxx.xxx.xxx.1 inside the gateway, dynamic fails. I see here Priority: DEFUNCT.
When i entered the tunnel-IP, the defunct changed to the preset priority and its working like a charm too.
Is it my fault (eventually not understanding the
"When assigning interfaces, gateways can be added to them. This is useful if balancing traffic across multiple tunnels is required or in more complex routing scenarios. To do this, go to System ‣ Gateways ‣ Single and add a new gateway. Choose the relevant WireGuard interface and set the Gateway to dynamic. These scenarios are otherwise beyond the scope of this how-to"
or did i find a glitch?