Flowcharts improvements; Instances Bar fixes; New demo game & more.
It's not possible to detect features that are not compatible, as the older version doesn't know they even exist.
An error is enough to know something isn't compatible and the user can troubleshoot and/or disable those events. The fact that I can manually copy one project to an older one is proof that it is possible and I have been doing that for many years.
All I am saying is, the copy process is time consuming and it needs to be copied in the correct order for it to work. If that was slightly automated it would benefit the user significantly. You are getting hung up on "This is a beta". This has usages more than just rolling back to older versions it's also very helpful when you want to copy certain things you built between projects which very often are from different versions.
It's not possible to show an error for features that are not compatible either. Doing so means using a time machine to predict what changes are made in future and ensure a useful error message is shown for them.