I've just found a page for the synology server on portforward.com so I'll give that a try.

Thanks

I used to open port for my Xbox according to this link tp tech sent to me:
http://www.tp-link.com/en/article/?faqid=71
Maybe it can give you some clue...

Thanks.

I've checked that page and port forwarding.com and still can't get ports open.

I describe what i see at 1043nd:
virtual servers-add;
service port: this is for outside; so be it 58900 ( your NAS has it in it's documentation) or 58900-58910;(or 80 or 21 see the documentation)
internal port: 58900 (or 80 or 21 see the documentation)
ip address: it is the ip address of NAS
protocol: all
enabled;


See also that the NAS has the static ip adress ;

DMZ means that the pc (or NAS), indicated by the internal ip address is outside of firewall;

After you set that, maybe is a good ideea to reboot the router.
Maybe you can start with that, and your previous settings will work.