Hi eladts,
as I can read from your very first message, the tunnel seems to work and the problem is just that you don't get IPv6 addresses for your clients within your LAN/WLAN. If you install frimware 1.02 and end up with the same problem, do the following:
For testing purposes you could try to configure one of your clients within your LAN manually. With the known prefix <PREF>::/64 where <PREF> must be the same first 64 bits you entered into the field "LAN IPv6 address" at the "IPv6 in IPv4 Tunneling ()" configuration page of your Router, you could manually configure the addess <PREF>::2 for use on your client. Next you configure the IPv6 default gateway which must be the link local address of your Router. You can see this address written in the field called "LAN IPv6 Link-Local Address" at the "IPv6 in IPv4 Tunneling ()" configuration page of your Router (fe80::...). You should have configured an IPv4 DNS server so for a quick test you don't have to configure an IPv6 DNS server because any DNS server can resolve both IPv6 and IPv4 addresses no matter what transport protocol (UDP/IP or UDP/IPv6) is used to ask it.
After that manual configuration try if "ping ipv6.google.com" works. If true, you now at least know, that there is a problem with stateless address autoconfiguration (SLAAC) and that your tunnel works. If false, go to the "Tools | System Check" page of your router and do an IPv6 ping test for ipv6.google.com or its IPv6 address 2a00:1450:4016:800::1010 in case there is a DNS resolving problem. If this test fails anyway, your tunnel doesn't work, otherwise there must be some other unknown problem.
In order to analyze the SLAAC problem a bit deeper, your could install Wireshark (also install WinPcap, if I guess right that you are using Windows? During Wireshark installation you are asked if you want to install this, too). Now start a packet trace listening on your LAN or WLAN interface, whatever connects you to your router. Before, you should have entered the filter expression "icmpv6.type==134" into the filter field and press "Apply". So you will only see the Router advertisements of your router. Be patient! Maybe you have to wait up to 15 minutes to see a first packet arrive. If no packet arrives after about half an hour, the probable problem is that your router doesn't send router advertisements. Hence SLAAC isn't available for your clients.
If a packet arrives, analyze the ICMPv6 protocol fields: The "Router lifetime (s)" has to be greater than 0 (it should correspond to the value "Router Advertisement Lifetime" times 60, which you had confgured within your router), otherwise your client doesn't configure the link local address of your router (fe80::... the ipv6 source address of the packet) as a default gateway, hence it can't route IPv6 packets destined for the IPv6 Internet to your router.
Next check the Flags of the ICMPv6 packet: The "Managed address configuration" flag must be set to 0, otherwise your client tries to get an IPv6 address via stateful DHCPv6 which is not supported by your router as far as I can see from the manual.
Next there must be an option for the advertised IPv6 prefix according to the above mentioned <PREF> value. Consider the flags within this prefix option: The L- and A-flag both must be 1. If A=0 the client doesn't form an own IPv6 address from the advertised prefix. Finally check, if the "Valid lifetime" and "Preferred lifetime" both are greater than 0. With a "Valid lifetime"=0 the client again will not try to form an own IPv6 address (same as with A=0).
If anything I described turns out to be wrong you have found the reason of your problem and did the job the D-Link engineers should have done.
PT