I have been trying to get the DMZ on Port 4 to work - under LAN>>General setup. The Dashboard shows the Port 4 is configured as DMZ when a device is connected. Two problems (at least)
1) DHCP to acquire a network address from a Windows PC is very slow (more than 30 seconds). DHCP from a MacBook doesn't work at all - the Macbook just shows a self assigned address and I have to set the address manually. I am using the default DMZ address 192.168.254.1 and the PC/Mac have address 192.168.254.10
2) Once connected I cannot get any outbound traffic to work from either device despite having set a Route policy to forward traffic from 192.168.254.10 to WAN1
Firmware is at level 3.9.4.1_BT
I am assuming I am doing something wrong - does anyone have ideas please?

An update for anyone who might be interested. It seems that the upgrade to firmware 3.9.6 (applied on 19/4/21) has fixed this.