If you have issues with the engine, make sure you're using the latest available version. You can update the main package inside the Unity editor using Asset Store window. In case you're using any of the engine extensions, download the latest packages using following links:
If updating didn't help, try to re-install the package by deleting
Naninovel folder from the project and re-importing it from the Asset Store.
Always remember to backup your project (or use a VCS) before updating or deleting a package.
Haruhi God knows what could happen in the process.
ʕノ•ᴥ•ʔノ ︵ ┻━┻
Join our official Discord server to chat with other Naninovel users or send a private message to
@Elringus#6359 for the direct developer support.