Just set your IP manually. It doesn't hurt the router.
after having (under cmd.exe) done on XP side :
ipconfig /all
take a free IP in the same range as your XP actual IP.
that is :
if your XP has the IP : 192.168.0.5
give your Amiga the IP : 192.168.0.10
(set the same mask : 255.255.255.0)
the gateway is the router, so set gateway with its IP.
usually : 192.168.0.1
