Creating an .txt file for every entry dynamically I'm looking to create a .txt file with table field data taken from an entry on the fly. All entries would have their own designated files. It's for video chapters with JW Player. They ask for a .vtt file but with testing a .txt seems to work.

I've had a good search but can't seem to find much. I guess the worst case scenario is uploading them via FTP, but preferably not! Thanks.
You can write a plugin that listens to the onSaveEntry event.

When that event fires, you can grab any of the data you need for the text file from any of the custom fields and your plugin can write it out to the filesystem at whatever place it needs for JW Player to consume.