aaP_gr33nday: Thank you so much. That worked.
For those like me that need all the help they can get to understand what to do with this: -
In the command line:
sudo nano /etc/rc.local
In rc.local file I inserted the following line at the end of the file but before 'exit 0' :
service bt_ddns start
Saved and closed the file, rebooted and on startup DNS service was running.
Thanks again.