you dont really need to use hamachi since normal online works fine
Unless you're behind an ISP controlled NAT like myself, then in any case it will not work and you will have to use Hamachi.
By the way if you're unable to see your Hamachi friends games you will have to set the Hamachi adapter to be in the first priority.
See this link to learn how to set up any adapter to be the first priority adapter.
Link
The same trick works for Windows XP also.