Re: Simplified Chinese doesn't support mods
@agathayin If you're referring only to the mod interactions, then this is an issue for mod creators: they need to add translation strings for simplified Chinese. If you feel comfortable enough with the languages, you could even offer to translate the text for your favorite modders—I'm sure at least some of them would be happy to have the help.
If there are any issues with vanilla game functions, you can try the troubleshooting steps listed in the first two posts of this thread: