IPfire behind router&port forward from public IP to internal server

I’m trying to make a rule on my IPfire to acess an internal server on port 22, from a public IP adress.
I’ve made an trial-and-error, but still can’t make it.
Note: I’ve changed my Ipcop server to Ipfire, so the problem is not on the router.
Here’s my network & firewall rules:

Thanks fr your help!

This is what I would try:

Source: Standard Networks, Red.

Check NAT, and DNAT. Firewall interface: automatic.

Destination, check Destination address, internal IP running the service on port 22

Protocol, preset, select SSH (or, protocol TCP, destination port 22, the rest blank).

See this as an example: wiki.ipfire.org - Forward Port 80 from Any network to Green

General documentation: wiki.ipfire.org - Creating Firewall Rules (reference)