11.4 -> 12.3 updated system fails to route traffic after reboot?

Have a firewall box with three interfaces:

eth0 -> DMZ, public 206.n.n.n
eth1 -> Internal, 10.0.0.n
eth2 -> External, public 75.n.n.n

The box was build with 11.4 and ran fine for many years; it was recently upgraded to 12.3, and continued to run after the upgrade.

Unfortunately, it took a power hit today and now refuses to route traffic! At the box, access to DMZ, Internal, and External is no problem.

ICMP from Internal -> External is acknowledged by the firewall (? - ping with firewall on stops at the box, ping with firewall off times out); no traffic is being passed from Internal to DMZ *OR* External interfaces, firewall on or off. Interestingly enough, ssh from Internal -> DMZ shows "Connection refused" with the firewall running, but times out with it not running?

Nothing has been logged in /var/log/firewall since the upgrade even with "Log All", .. and "IPV4 forwarding" shows "Unknown" in "Security Overview".

Has something changed with 12.3 that cause this type of problem? Is "IPv4 Forwarding Unknown" a problem?

TIA!

Lee