Hello. (While I was typing this, Ronski posted. I thought I would post anyway,
because I say a little more that may be helpful).
The "normal" thing to do is set your router up something like this:
inet addr:192.168.1.254 Bcast:192.168.1.255 Mask:255.255.255.0
Without any fiddling, the HG612 will occupy 192.168.1.1 (it might be worth setting that statically
in the routers dhcp settings).
Then it Should Just Work, although there might be various things cached in the browser you are using,
or elsewhere which you should somehow flush. Check you can ping the modem at 192.168.1.1
and the router at 192.168.1.254. You should be able to telnet or ssh into both.
I believe there is some more "elegant" way to organise things, that you can find somewhere on kitz the kitz site,
involving setting up both 192.168.1.* and 192.168.2.* , but my memory and searching foo are not great.
If I were you, I would go for the inelegant, "normal" 192.168.1.* setup, at least to begin with.
[EDIT] Regarding "elegance", some links are at the bottom of this page:
http://www.kitz.co.uk/routers/hg612unlock.htm.
Another page that seemed to address a similar point (and put the word "elegance" into my head) is here:
https://support.aa.net.uk/Router_-_EchoLife_HG612. I've not tried "one wire" myself.
Try not to reboot your modem too often while you are fiddling about. Ideally, when you power it down or
disconnect the vdsl cable, leave it so for at least 30 minutes. (I'm not sure, but similarly, when it's
synced, leave it so for at least 30 minutes.) Otherwise DLM may kick in soon, and start to damage your crispy
new speed test results.
HTH, some.