Hi TD,
Sorry it has taken this long to reply it has been a very hectic day.
All the comments so far are right and ring true. We do have a custom Firmware but it is used for TR69 only. This allows the modem to call the server and pull template instead of needing you to configure it. If you use the standard model which can be bought from a lot of placs then you can download a Template from our website allowing you to easily setup either NAT or Routed IP. Other than this, our templates have the standard VPI and VCI set into them and also have the modem set to PPPoA.
Do note that Kitz is right however, the Zoom is certainly better than what you have and there is no harm in trying it.
Kindest Regards,
Leo