I am lost. You wrote that you have a static I.P. from your ADSl provider.
That will fix all your troubles.
You will not need anything in betwen your ADSL modem and the Quintum.
I am asuming that your ADSL provider gives you the ADSL modem.
I am asumming also that the ADSL modem have a ethernet conection. eight pins on a flat cable (RJ45).
If all that is true, all what you need is a cable from the ethernet port of the ADSL modem to the Quintum A800.
Enter the I.P. given to you by the provider on the Quintum, enter the default gateway and mask information and you should be able to put the Quintum online.
Is something else diferent on that place???
Where are you located at????
Only four tylenol every four hours, even if you drink to forget the troubles.