Looks like it's an issue with BetterButtons, if you disable it, it allows you to save etc but means there's no draft mode
yeah that was the default scaffolding before we decided to use better buttons for it
is there a hook in the betterbutton thats not being set up correctly?
So I don;t have much more time to spend on it, but it looks like it's irrelevant to catalogmanager and is just with betterbuttons, if you install better buttons, add a modeladmin to manage a page type then edit that page type it will flunk out
I look forward to troubleshooting that sometime in 2018.