Local Play

[Cucoo5]

Hamachi makes port forwarding easier (or w/e it really does...)
if you both have hamachi, use it to create and join a network, then see if that does anything
if the LAN doesn't work, you then could do something a bit more interesting and use the server program for minecraft.

[Ahrzayl]

What's this about a server program? How does that work? o.o

[Cucoo5]

ok it's the server.exe that you can get from the minecraft download page. It's the 'vanilla' version of how to host servers (without all the fun plugins). With hamachi (which is still the only means for me to host my own server...) you can use that and have your friend connect to the map as an actual server. The only thing you need is the network IP from hamachi, make sure that hamachi is set to the right port for Minecraft, and then you just fill out the information for the server properties file then you do a bunch of other things that I can't really explain clearly cause I'm about to pass out here...

but ya it's a possible means to set up your map so that you and your friend can play it.
It's relatively straight forward, I can give ya a basic idea of how to go about it with hamachi...
if anything, hamachi is the trickiest thing to set up for this set up, just because you gotta make sure you create a network with the port. other than that it's simple enough. There's a handful of tutorials that show how to do it "normally" (w/o hamachi), but you have to know port forwarding...and I can't help there cause I could never get it to work.

Anyway...the network create and server properties is the main deal. and then you gotta import your map from the minecraft save location to the server folder.

[Madvicius]

Did you check if UPnP is activated on your router after you've port forwarded everything needed ?