Port Forward from no default Gateway problem

I have router with 1 default gateway (for internet), and another gateway with public IP address.
I would like to make port forward from public IP address to local, but not working because of different default gateway.

I’m try to setup this with connection mark, on inbound port (public), and make routing mark (to route on public gateway) but not working.

Please hints…

Is there a default gateway defined in the VRF(routing mark) in question?

Here are config..

/ip route
add distance=1 gateway=10.50.0.1 routing-mark=ZG
add distance=1 gateway=192.168.10.2



/ip firewall mangle
add action=mark-connection chain=forward connection-state=new in-interface=\
    pptp-out1 new-connection-mark=connection
add action=mark-connection chain=prerouting connection-state=new in-interface=\
    pptp-out1 new-connection-mark=connection
add action=mark-connection chain=forward connection-state=new \
    new-connection-mark=connection out-interface=pptp-out1
add action=mark-connection chain=postrouting connection-state=new \
    new-connection-mark=connection out-interface=pptp-out1
add action=mark-packet chain=forward connection-mark=connection \
    new-packet-mark=packet passthrough=no
add action=mark-routing chain=prerouting connection-mark=connection \
    new-routing-mark=ZG