In order not to harm my brain10 files, I created a new, empty file in Beta11 and imported an brz file created for this specific purpose.
This was the ONLY FILE I played around with while in Brain 11.
And now, when I started Brain10 in order open my usual work files I'm getting this message:
You should update to Brain 11.0 to open this brain.
I really don't know what to say. How can you publish a Beta version that immediately takes hostage of all the brain 10 files (WITHOUT explicitely opening them)?
I'm now getting back to an 2 days old backup, but not before deinstalling this Beta.