Thats your subwoofer amp correct? Just use the rca subwoofer out from your receiver and plug it into the amp on the back of the subwoofer. Hook your speakers up to the correct binding posts on your receiver NOT the subwoofer amp. Do not use the speaker terminals on your subwoofers amp.
All your speakers should hook in to the correct binding posts/clips on the receiver.
So hook the front speakers Left and Right to the front left and right on the receiver.
Same goes from the rest, center speakers goes to center channel binding posts label.
On the back of your receiver NOT subwoofer, you should see a RCA output thats labeled LFE or Subwoofer channel. Take your RCA and plug into that and then into the subwoofer amp that says subwoofer in the white colored RCA input. Then switch it to Digtal receiver 5.1 ect (Not Pro Logic) . Set your subwoofer dial to 80hrz with phase at 0.
Set all the speakers to normal not biamp, then just set them to small then since you can't do individual crossovers for each. During the Arx break in you can run them as large at lower volumes that will help give them some bass to break them in.
Don't over think this. Break in isn't a big deal to worry about if you can't get everything exact. It just takes them awhile to start sounding better.
Hope that helps.