I did not see that there were new comments until now as I wasn't notified by itch's notification system, so I apologize for this late reply. I have subscribed to this post so I will be notified from now on, but consider joining the discord and tagging me there instead for faster responses.
You need to update your nwjs versions if you are using the MV version of the plugin. The plugin uses es6+ syntaxing that isn't usable with the default nwjs version that MV comes with. You can check this link on how to do that.