network trouble after flashing router

I originaly had a Linksys WRT54GS v1.1 router, I have been using it for years and it has been great. I have been runing my xbox 360 via my laptop to have a wireless bridge to the network as it's on another floor but don't like haveing to use my laptop for this so I bought another Linksys router to put DD-WRT on it.

I bought a WRT54G but I didn't realise it was v7.0, which cannot be flashed to run DD-WRT. I did not think this would be a problem as I could just use this to replace the old one and flash that.

Firstly I had a lot of trouble getting the router and my modem to communicate (resorted to re-setting them both symultaniously and that seemed to work) and then I proceeded to flash the WRT54GS.

I have followed the following guide to the letter (http://www.dd-wrt.com/wiki/index.php/Linksys_WRT54G/GL/GS/GX#v1.1) on how to set this up as a bridge.

the bridge DOES work, I can access the flashed router wireless from another room and it's all seemed good, however, when I tested it with my 360 it would not connect, it got stuck on the "network" part of the test. It seems the bridge is working however the flashed WRT54GS does not want to communicate with anything else. Thinking this may be due to the setting on the xbox I used the laptop to try and search for solutions. The laptop now will not connect to my home network, it has its status as connected but will not connect to the internet nor allow my regular use. I'm not sure but I think I must have some settings different on the new WRT54G.

I have not checked if the PS3 or Wii will connect to the network now, the Wii I rarely use on-line and the PS3 I have only just thought of.

I don't really know that much about networking and my friend who works in the field won't be back for several weeks to help me.

I'm sorry if this is a common query or if I have posted in the wrong place, I have searched the forum an could find no solution.

I'd be greatful for any and all help you could give.

laam999