Made the second server and wanted to upload a custom world. Its a custom superflat with no blocks (kinda like space) and the process is very confusing. Tried following the tutorial, managed the file.io, but it tagged the world as a separate dimension. In other words, if i want to join the World, i need to join the server, and then write ton of commands to just teleport to it, and the spawnpoint just doesn't work. What do i do to completely change the default normal world to my custom (zip file) ?