How to enable IPV6 and DHCP6 on a Fortigate firewall with FortiOS 5.2

Example Environment:
My IPv6 Subnet: xxxx:xxxx:0:106::1/64
My DHCP Subnet: xxxx:xxxx:0:cccc::1/64

Step 1. Configure external interface and set options:

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config system interface
    edit "wan1"
        set alias "External"
            config ipv6
                set ip6-address xxxx:xxxx:0:106::2/64
                set ip6-allowaccess ping
                set ip6-manage-flag enable
                set ip6-other-flag enable
            end
    next

Step 2. Configure IPV6 Routes:

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config router static6
    edit 1
        set device "wan1"
        set gateway xxxx:xxxx:0:106::1
    next
end

Step 3. Configure Internal Interface:

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 config system interface
    edit "Internal"
            config ipv6
                 set ip6-mode static
                 set ip6-address xxxx:xxxx:0:cccc::1/64
                 set ip6-allowaccess ping
                 set ip6-send-adv enable
                 set ip6-manage-flag enable
                 set ip6-other-flag enable
                 set ip6-max-interval 600
                 set ip6-min-interval 198
                 set ip6-link-mtu 0
                 set ip6-reachable-time 0
                 set ip6-retrans-time 3000
                 set ip6-default-life 1800
                 set ip6-hop-limit 0
                 set autoconf disable
                 set dhcp6-relay-service disable
            end
    next

Step 4. Configure DHCP6 Server And Options:

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config system dhcp6 server
    edit 1
        set dns-service specify
        set status enable
        set interface "internal"
            config ip-range
                edit 1
                    set end-ip xxxx:xxxx:0:cccc::6000
                    set start-ip xxxx:xxxx:0:cccc::1000
                next
            end
        set lease-time 10800
        set option1 0
        set option2 0
        set option3 0
        set rapid-commit disable
        set subnet xxxx:xxxx:0:cccc::/64
        set dns-server1 2001:4860:4860::8888
        set dns-server2 2001:4860:4860::4444
        set dns-server3 ::
    next
end