I have opened ports on my router. 6112-6119 but i still can no connect to b.net.. any suggestions??

Anti-virus\firewall. Im use router (ofc wi-fi) and do not configure anything for this new old blizz games. Most games work for me "out of the box". I have error that i have bad connection, but only once.
You cant connect to Bnet at all or cant start game with someone?

Looks like fixed in discord.
Wrong CD-key typed.

Be careful while typing the CD-key!

I had trouble as well, got a web ticket to figure it out. The MOD told me they couldnt really assist since it was based on Windows firewall. They gave me an idea what to do though, I mostly fixed it. Everytime i login, i still get the error. I have to relog in for the port to open. There is prolly a "better" fix, i just relog in everytime after the first attempt. Also not sure if anybody knows, WC2 had a "spawn install" for game owners. Does this version have it as well? Spawn install is able to install multiple Comps to play b.net as well. Only difference is that other players cant host or play campaign i think.

As i understand, spawn client is not supported on GOG server.

I didn't understand, what exatly error you get.
But try to join .ru server to check if the problem is related to GOG server or your local computer.
How to join .ru using GOG war2: http://en.war2.ru/support/moving-from-gog-server-to-server-war2-ru/