Sorry, should have got back and updated this thread.
There is a problem with 1.2.0 if you are using WAN with IP Alias setup in that the sync between units is wrong and is confirmed by DrayTek and it does leave the relevant NAT Port-redirections disabled. If no IP Alias's are setup then the firmware 1.2.0 should be ok.
I have tested a beta release and the problem is now solved.
Hopefully the fix will be included in the next full release.

Neil..