Today's Progress!
We've got the master server up and running and it does everything but finally connecting the players together! We've got a suspicion on the cause (possibly still a NAT / port forwarding issue) and are still investigating.
However, since LAN technically does function, we've decided to let LAN users try the build out while we debug the master server issue! Please follow the instructions in the forum thread here and check back frequently for updates!
Multiplier! Erm... Multiplayer! Hurray!