You shouldn't need to put your VPN IP anywhere in the server, by default I'm pretty sure it listens on all interfaces. Just the client config I imagine is sufficient
Ah man that was just tested. I'll put that on my todo list.
In its simplest form, without containers, are you able to run the server and connect to localhost using the official launcher? (There's a setting to swap from stable server to local server)
Unicode? Sir this is C, if the character doesn't fit into a uint8 it's scope creep and too hard