DLink 2750B Modem/Router not assigning DNS

[dshafs]

I just received thiis device as a replacement for my old Westell 6100.  It was becasue I had to reboot modem daily.  That problem is still unresolved but this one is frustrating.  I know my way around routers pretty well having been in IT support for 20 years.  Anyway - I want to use a DNS server on my network instead of the DNS provided by the Gateway.  This device like almost every other has a configuration setting for this on the DHCP page.   Everytime I set it to the DNS server IP on my network my clients DO NOT receive DNS servers OR if they have IPv6 protocal they recieve f0:00:.....  1% which I understand to be IPv6 DNS but does not work.   

If I use the Gateway DNS I am fine but then lose functionality on my network.   I have been on PREMIUM Support with Verizon and they said they cannot support or answer any questions that do not concern Verizon gateway DNS servers.

THIS IS BASIC functionaliy.  Anyone have this problem with this device.

Thanks !!