the mod for the map nyrandil not working is there an issue with the mod?
I'd suggest going to the mod steam workshop and check on it. Since it's a steam modder and not the hosts issue.
The "Bad Mod Map" error message can also mean that a mod you have on your list of mods is no longer on the Steam Workshop.
As the mod system for ARK simply was just maps to start with, the error message "Bad Mod Map" is a holdover from WildCard not updating their error handling