Setting your Draytek Vigor 2760 (or 2760n or 2760Vn) to respond to pings from the internet isn't very obvious. Note this was on my 1st gen 2760n, so firmware v220.127.116.11 - hopefully the 2nd gen with v3.x.x firmware series works the same way. I don't have one to hand to check, so let me know ...
Normally on a Draytek (such as 2830, 2850, 2860 etc) you go into System Maintenance > Management and untick the 'Disable PING from the Internet' box. On the 2760 series that check box doesn't exist. Its still the same menu option, so:
then for Management List you have to click the + symbol
and move the 'Ping' item from Available to Selected,
for your specific Internet interface (in this case the DSL PVC1)
Simple when you know where to look for it, see diagram.
Note that its worth leaving this off unless you're using it for testing or maybe uptime monitoring.
The other interesting point about the different models of the 2760 is that the older firmware model supports remote dial-in VPN users, whereas the newer v3 doesn't (I think it has LAN-LAN VPN iirc).