Private address on WAN nat not working?

[vibrion]

Hi!
I'm coming from pfsense world to give it a try to opnsense. I'm having a small problem trying to access WAN right from private address. Of course these options (RFC1918/Bogons) are unchecked but still can't access to a simple port forwarded  port 80 on DMZ (obviously coming from another private address, but it let me ping to it).
This setup is because i'm still in lockdown upgrading to a new firewall/router equipment, so my AP is behaving as DHCP to WAN.
The strange situation is if I fake a public address (both WAN and another PC) it allows me to reach server behind DMZ. I'm missing something? Of course this is more to make setup more comfortable
Thanks in advance
Martin

[vibrion]

Almost ten days and no single reply??? So few experts ?