Hello @yogasynergy,
Thanks for writing in! I have checked your site and I can confirm that there are a bunch of JS errors in the console. This is the cause of the issue. It may have came from one of the installed plugins on your site. It could also be caused by a plugin conflict, amongst other things. Please check out this troubleshooting article here and follow the instructions for the following sections (where appropriate):
Testing for Plugin Conflict
Child Theme
CSS/JS Customization
When Editing the page, you should be using the “Cornerstone” tab or the “Edit in Cornerstone” button especially if the page was created in Cornerstone. Be advised that you cannot edit the page created in Cornerstone with the WP Editor. All your contents will be corrupted and you will not be able to edit the page back in Cornerstone.

We are looking into the issue wherein the widgets are not loading in the selector. So far, it is working as expected on our local testing servers. It could be caused by a plugin conflict or because of the JS errors in the console.
Best Regards.