Weird. The loopback thing is supposedly only for debugging and configuration.

Quote:
Enable / disable the loopback interface. The loopback interface makes your internal clients appear as if they are external. This is useful for testing things like DynDNS names. The loopback is an option because enabling it will break PPTP and Windows machine browsing by wireless clients.


I've found it always breaks stuff when enabled like slimserver and DNS. Everything appears to be coming from the router itself which makes stuff go strange.

You've got the MAC addresses entered on each side properly in the WDS screens?