So what's all the stuff about NAT translations, etc. Brief summary.
Short answer: you don't have to worry about it.Long answer: if you want to worry about being as network-bandwidth-efficient as possible, run one node normally, and run all the rest with the -noirc -connect=IP.AD.DR.SS flags so they connect only to the one 'master' node. All the network traffic will then go through the master node.