Hello @yowga,
I would highly recommend that you create a staging site. This is very useful so that we can test drive any X updates like X 6.1.6 and Cornerstone 3.1.6 in the staging area, do the troubleshooting without disrupting your live site. Once everything is perfect, you can easily and flawlessly proceed the update in the live site. To know how to create a staging area, please check out these articles:
And by the way, in some cases, caching is causing an issue with Cornerstone which is why after any X and Cornerstone updates, clearing the plugin cache, site cache and the browser cache would help in resolving the issue.
Please let us know how it goes.