modem problem (btc inside) [SOLVED]

Hey guys!

I bought a blockerupter cube (30gh) and plugged it into my modem.

It's a thomson TG585 v8 (wlan modem).

After looking on the web the miners ip i found 192.168.1.254 and 192.168.1.254:8000. I tried both but i couldn't connect to the "interface" to set pool details and so on up.
So i tried to connect the the standard gateway from my modem. i found the ip in cmd with ipconfig. i still couldn't connect. not even to my modem-wlanrouter. (192.168.1.254)
I phoned my internet provider and he said that they don't let us to connect to the modem. i dont know why and i don't care.

i've got an old netgear wlan-router connected to internet (=modem i told you before) via an electrical socket. my pc is connected by wlan to the netgear router where the miner is plugged in via lan.
i tried to connect to the miner again with same ip but it still didn't work. the router ip is 10.0.0.1 But at least i am able to get into the routers interface!
i think i can't set it to 192.168.1.XYZ because the modem is running that ip.

im working on this for like 2 weeks now but i am not able to solve this. im very thankful for any help to get that thing running.

the one who can make this will get as much btc as the miner makes for 1 day (24 hours). promise!

greets from our wonderful planet earth

Edit:

I disconnected my pc from internet, i reset the cube and plugged it into my pc by lan. then i was able to get into the miners interface to set ip. then i was able to connect it to my router and
get into the "interface".

I hope this will help, if there are any questions feel free to ask me.