I don’t understand what you mean “Revision”? Contents lose while working/editing page.
I know very well what is cma_layout_data and I’m advanced WP user. After create page in the CM, I update page and then copy all contents from the Value field. Next, if data lose I try put content back. Since it does not work, I need to update the appropriate record in the database and everything is fine, but this is not the solution.
Important note, sometimes when problems with CM occur, CM tab isn’t visible (attachment).
Web page work well. I just need to repair errors in the CM. That’s all. I’m waiting patiently for the update.