Try leaving DHCP Enabled and using the "Alternate Configuration" settings. You only need the IP address, Subnet mask and default gateway. Do this also for any other machine. You dont have to mess with the WINS settings.
This is how the wired cards have been configured, so when they are crossed it resorts to the set IPs. Net discovery is on.
I do know that some networked games have software protection to stop multiple copies for the same installed disk being detected. In other words you have to have a licesned game disk for each machine.
I suspect this is it problem causing that assertion error in IWD.Unfortunately my router only allows me to reserve an IP on the device name which is crap if a machine has more than one device, but i will double check this.