WL-500gP V2's subnet ID and the subnet ID in WAN are the same.
reflashing my wl500gpv2 with all versions of firmware images from http://support.asus.com/download/ but unfortunately could not login to no one of them with default user/pass admin/admin to web interface. Also tried some standard combinations root/admin root/root root/password ..
1. pull power cable and wait 20 seconds
2. keep button pressed and connect power cable: power led should flash
3. ping 192.168.1.1 should reply else redo steps 1 and 2
4. run Asus Firmware restoration tool, select firmware file (e.g. wg01080109_WL500g_EN.trx) and press upload.
After some seconds press the Abort button or wait until it says "Upload fails! Please check the connection"
5. from a dos box or linux console run: tftp -i 192.168.1.1 put wg01080109_WL500g_EN.trx
6. tftp returns something like: "Transfer successful: 3731456 bytes in 2 seconds, 1865728 bytes/s" if it doesn't redo steps 1-5 (sometimes I needed three or four times before it worked)
7. after ca. 80 seconds your Asus should reboot
I did this procedure with
Then I could flash any firmware and the device was alive again.....