This will NOT work across different houses unless you set up port forwarding (which is pointless with cracked games because your external IP changes often). Use Radmin (Method 1) for friends in other cities.
The most common "death" for multiplayer sessions wasn't a zombie bite, but a version mismatch. If the host was running Build 41.65 and the guest had 41.73, the connection would instantly fail. Survivors had to ensure every file, mod, and build number was identical across all PCs to maintain the delicate digital link. set up a dedicated server for better performance, or are you looking for a list of essential mods for a co-op run?