As far as I know the option should consistently be called "Gather Debugging Information", not specifically a reference to logging. If there's somewhere we've documented that it's explicitly a logging option, let me know because that's probably a documentation or UI bug.
I'm not sure exactly what "techpreview.cfg" message you're seeing, but if it says something like:
DictionaryLoad: Cannot open file techPreview.cfg
That should be a harmless message. Our log-files aren't really intended to be fully user-readable, so most of the message in there are aimed at our developers to help troubleshoot problems.
