Messages

As you've found, leaving DNS servers blank in a scope will just "push" the interface IP to the clients as their DNS server. I believe you could use the DHCP reservations feature for those couple clients and assign those non-standard  DNS servers specifically to those reservations.

[Add associated filter rule]

When you create the NAT port forward rule, the last option, Add associated filter rule, will create the filter rule on the interface automatically. Then you need to move it up in the chain before the LAN to any rule. Works for me.

Ex pfSense-r, IPFire-r, Smoothwall-er, Sophos UTM-er, etc here. :o Literally tried them all before finding my way here.
Brief search turned up nothing specific so...
What possibilities are there to provide better reporting for both proxy and URL filtering? Getting some strange behavior on some sites and am trying to isolate where the block is occurring so I can whitelist URL instead of removing category block. Categories blocked shown in attached graphic.

Thanks for a great product! :D