I hope you turned dyndns off on your sme. Also you should assign a static value to the wan port otherwise all your port forward settings in your router will become useless after an address change.
This statement was based on the dyndns vaules changing from 192.168.1.110 to 192.168.1.103.
I haven't read the manual for your router, but generally speaking you sould set a value outside the dhcp range to the wan port of the sme and set that value in the default dmz in your router.
Of course you could always do what I recommended in the first place and let your sme do what it was designed for in server-gateway mode. I think it would have solved all your problems much faster.