syslog-ng configuration-What am I doing wrong?

[GiUnZ]

I have installed an OPNSense firewall and configured with the following plugins and/or services:
- squid for transparent web proxy
- ClamAV and C-ICAP
- Unbound DNS
- Nginx with naxsi enabled
- IPS
I have configured  in the logging/targets a syslog udp to forward to visual syslog server without selecting an Application , Level or Facility.
In the server side, i  filtered out filterlog tag I cannot see any another logs even after restarting the service or the whole firewall. From the firewall UI, I see logs normally.
I am looking for a tutorial that helps configure the above so that I can send my logs on whichever server I need to. Is there any known bug that i was not lucky to find, about this?