Are you using auto-detect? 

Where is Auto Detect located with GUI ???

If you wish to setup the IPV6 in G54, I suggest to follow the steps in the below given link:

http://arris.force.com/consumers/articles/General_FAQs/G54-IPv6-Address-Setup

Yes I have Enabled the IPv6 with App but nothing populates with website 192.168 with Local lP IPV6 Addresses.

So after being on the phone for over an hour with ARRIS Support they could not get the IPv6 to work and said to call comcast. Did that and Comcast Re-Provisioned the G54 and still not working. Paid $600 for this and cannot connect to IPv6. Anyone with comcast have this working???

So after calling Arris again and them telling me it's a Comcast problem with IPV6 not populating the tech told me it's possible that G54 is compatible yet with Comcast for IPV6 and Arris ( The Manufacturer ) still needs to upgrade this feature. Can a Arris Moderator confirm or deny this? Hard to believe but the G54 is still pretty New.

IPV6 is compatible with G54. 

If IPV6 is not working on your device, I suggest you to contact internet service provider for further assistance.

I was on the phone 3 different times today with Comcast. Whatever I said they just could not add the IPv6 address. They Reprovisioned and still nothing. They blamed ARRIS was on the phone today 3 times today with ARRIS saying they don't add the IPv6 which sounds right. Comcast kept telling me because it's not one of their Gateways they can't add the IPv6 address. Don't know what else to do. IPV4 works fine and internet works.

With GUI under Decices it has Firmware upgrade is something that has to be done???

Arris develops the software update and makes it available to service providers.  The service providers qualify, test, and distribute the software update to devices on their network.  It has limited control or visibility on distribution by the service providers.

If you are unable to access the IPV6, you have to check only with internet service provider.