routing between multiple nic's

Hi
I'm using Vista Ultimate on a HTPC with 3 NIC's to route my traffic between
a backup pc and a Denon UPnP device.
For Media streaming, I'm using Tversity Media Connect for my UPnP devices,
and with the move to vista, the Tversity media servers shows up randomly, or
not at all. With XP it all worked ok.

Here's my list:
vista Ultimate
I switched off the Firewall and UAC completely
I enabled the routing and remote access service by default as my Vista is
also the router.
HTPC:
nic1 IP : 10.0.0.10/24 , GW: 10.0.0.254 (wlanrouter on ADSL)
nic2 IP : 10.0.1.10/24 , GW - ( backupPC)
Nic3 IP: 10.0.2.10/24 , GW - ( Denon receiver)

backup pc:
IP :10.0.1.1/24 , Gw 10.0.1.10

Denon IP: 10.0.2.15/24 , GW 10.0.2.10

The 'incoming Connections' properties, available in the network view after
enabling routing and remote access, set at ipv4 ' allow callers to access my
network' as it won't route if disabled

In Networks , Advanced, I put the 10.0.2.10 segment of the Denon as first in
line at the bindings view. Also, IPv4 at the top , and ipv6 disabled
Mediasharing WMP11 disabled

I configged al nics as private networks, and there;s no additional software
like antivirus or firewalls (first I need this to work)
Sometime it switches back to Public network though.

Am I doing something wrong ? It seems like the broadcast of the UPnP signals
doesn't reach the Denon at all, or just sometimes pushes through.

Thanks in advance !