Setting up DD-WRT behind a DSL router/modem from ISP

Okay so I bought a Buffalo WBMR-HP-G300H the first router/modem that supports DD-WRT, after having managed to get dd-wrt to run on the router without problems the next step was to plug my dsl cable from my isp into it. The supported adsl standards of my ISP are: ITU G.992.1 (ADSL-G.DMT) ITU G.992.2 (ADSL-G.Lite) ITU G.992.3 (ADSL2) ITU G.992.5 (ADSL2+) But when I access my DD-WRT setup page I can only see Annex A Annex A T1 Annex A Lite Annex A DMT Annex A ADSL2 Annex A ADSL2+ Annex L Annex B Annex B DMT Annex B ADSL2 Annex B ADSL2+ Annex M Annex M ADSL2 Annex M ADSL2+ After consulting https://en.wikipedia.org/wiki/Asymmetric_digital_subscriber_line#ADSL_standards Not much has remained clear in terms of which one should I choose or are even the ones I need available. My connection speed is 80/10mbit/s As this is the configuration on my ISP router/modem Encapsulation: 1483 Bridged IP LLC VPI: 1 VCI: 64 Bridge Mode: Enabled But regardless the dd-wrt router just does not work, the dsl just blinks periodically and that is it. Now the second thing that I have attempted to do is to just connect my dd-wrt rotuer to my ISP router but the two just do not play well with each other at all. I select the Automatic Configuration - DCHP I ve set the router IP ( dd-wrt ) to be 192.168.1.50 just to test things out, while the IP of the ISP router is 192.168.1.1 One strange thing to me is that when I select Automatic Configuration DHCP is that it is still asking me for the Annex Type VPI/VCI etc... even though I am just configuring the LAN ports on both ends. I am sorry if my description is not the best I really am, if you require additional information please ask I will provide it promptly. Thank you all for your time