If you haven't touched the story editor at all:
Do a generate definitions in the story editor.
Then do a build.
Do them in separate steps the first time, then after that you can do them in one step. You shouldn't need any custom scripts in there.
If you don't have character creation setup and working, then don't use the levels you inherited and just have the startup and creation level as your first map. You do not need to have character creation to publish.
I have a basic character creation tutorial here for standalone mods, but like I said you should not need that to just get it working.
https://docs.larian.game/Basic_Character_Creation