I'd almost give up HOI's MP while trying to establish a MP game behind a router, used the usual "port forwarding" tricks, DMZ etc, and no way.
Then I remembered of this little gem hamachi, in short using it you could play using the "local network" option in hoi, it uses the internet to simulate a local and private network.
The only drawback is that all players must use it, but it's really simple and easy to install and configure.
It's not a solution to all MP problems, but it's worth a try, for you that have a gaming group that simply can't start a mp game because of connection problems
Then I remembered of this little gem hamachi, in short using it you could play using the "local network" option in hoi, it uses the internet to simulate a local and private network.
The only drawback is that all players must use it, but it's really simple and easy to install and configure.
It's not a solution to all MP problems, but it's worth a try, for you that have a gaming group that simply can't start a mp game because of connection problems