What I noticed with both versions is that it will not allow you to set it to Autoconfigure IP - there is a message about UPnP

It will not allow you to set it to Autoconfigure IP (i.e. use ARMGR's built-in DHCP server) because you're using an automatically assigned IP address on the PC (one in the 169.254 range). This is what it refers to when it says "UPnP".

The network trace is exactly what I'd expect to see: it's looking for an IP address, but since the DHCP server isn't running, it doesn't get one and opts for a 169.254 address instead.

This happens twice, because of the two-kernel boot mechanism in the Rio Receiver.

Now, by the looks of it, everything except the HTTP communication is working correctly: it managed to boot the second kernel, after all -- which implies that the service location, portmapper, mount and NFS services are working correctly.

What is odd is that the portmapper service doesn't respond to the second request, or did you leave out that part of the network trace?

Do you see any HTTP traffic at all? Do you have XP's firewall turned on?

Basically, the boot process looks like this:

1. Power on.
2. Load the kernel from flash
3. Decide which of the HPNA or Ethernet interfaces to use (based on link at the Ethernet port).
4. Try to acquire an IP address using DHCP. Failing that, use a 169.254 address.
5. Issue a service location request (subnet local broadcast on port 21075). The response tells it where to find the NFS server (strictly speaking, the portmapper).
6. Issue portmap requests to find out where the mount and NFS daemons are.
7. Ask the mount daemon to mount the root filesystem.
8. Download the new kernel from NFS, double-boot into it. At this point, if we acquired a DHCP address, this is passed to the second kernel.
9. In your case, we didn't use DHCP, so the second kernel will (IIRC) try again.
10. We go through the finding portmap/mount/nfs server rigmarole.
11. This time, we grab the player binary and run that.
12. It issues a service location request looking for the HTTP server.
13. ....and so on....