26.7 NAT port map trouble

[bitdigger]

I made a fresh install of 26.7 with the latest upgrades available. I have a VERY basic configuration. All I need is what used to be called "NAT Port foreward" to a local host. TcpV4 only one Port to one host on the lan. Thats it.
The host can access the internet without issues. When trying to connect to the service from the WAN, the requests arrive (in the logs) but are blocked with "Default deny / state violation rule". Yes, sure, but why? I created an alias for the host with its internal IP as well as an alias for the non standard port to be used. Then I created a Destination NAT Rule like this:

Interface WAN, Version IPv4, Protocol TCP, Source Adress WAN Adress, Port any, Destination Adress "WAN Adress", Destination Port "the port alias", Redirect Target IP "the host alias" options "log" and "register firewall rule".

I played around with everything I could think of to no avail. I tried setting up a manual rule, and with manual and registered rule also tried by changeing those settings which are IMHO new in 26.7. Really all I could think of that could make sense but to no avail. I am trying now for several hours. I know, this should be stupid simple, but aparently I am stupid. I am really really frustrated to be honest and would be very happy if someone could point me in the right direction! The fact that 26.7 is so new and internet searches show the good old times where one could simply set up a port foreward does not really help either... Please help me!

TIA Markus

[dseven]

The source address will not be your WAN address - it'll be that of the client making the connection. You probably don't want to set that at all (unless you want to restrict access to just that source)

[meyergru]

Correct, the source address is NOT your WAN address. And if you want to rule out further errors in the firewall rules, use "pass" before you try something more difficult.