That didnt work out too well… This morning, SSH to ALL machines on LAN failed (Temporary DNS name resolution), the firewall was suspiciously slow (and not responsive), I couldnt reach the internet from any machine...
Deactivated all rules under OPT1, and rebooted the firewall, all is back to normal.
For now I will assume this is only a glitch in the firewall and not related to my OPT1 rules, unless someone can point out that it is..