в логах:
22:48:41 echo: firewall,info 1938: dstnat: in:ether1-gateway out:(unknown 0), src-mac 00:00:00:00:00:40, proto TCP (SYN), 85.x.x.x:25857->92.x.x.x:1938, len 64
22:48:41 echo: firewall,info 1938: 1938 srcnat: in:(unknown 0) out:<l2tp-Uchet>, src-mac 00:00:00:00:00:40, proto TCP (SYN), 85.x.x.x:25857->
192.168.112.117:1938, NAT 85.x.x.x:25857->(92.x.x.x:1938->
192.168.112.117:1938), len 64
ошибок по этим правилам нет.