I don't know why your calling it a dmz? You do understand that your dmz from your rules has full unfiltered access to your lan network as well as the internet.
And unless you need to do something really odd, the automatic setting for outbound nat will nat your other segments you create - there is rarely any reason to change to manual outbound nat unless you have to do something out of the norm.. Which having another lan segment or "dmz" as you want to call it is not out of the norm.
A "dmz" is normally a network segment between the public internet and the private secured network.. Or just a segment that has filtered access between the public networks and the private network.
In your above rules you have a firewall between your dmz segment and your "lan" segment - but your rule base is wide open.. Normally you allow traffic from your lan into your dmz, but you do not allow unsolicited traffic from your dmz into your lan - which is what your current rules are.
example my dmz segment can not talk to my lan or my wlan or networks via an alias that has those local networks in it. Unless the lan or wlan IP started the conversation.
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