Not sure why I want to go back to the classic editor as it is being dropped. Bento was my choice for the new block editor, but now you are saying go back ???
This from SiteOrigin:
When you get a moment, please could you reach out to Bento and let them know about this problem. The issue might be related to admin-scripts.js. If I prevent that file from being enqueued in Bento, the SiteOrigin Layout Block works. They can perhaps look there first. I’m sure they’ll be able to resolve quickly once they know about the issue.
I know very little about web design, just trying to use the tools available and moving forward, not backward.