Multiple instance settings management

I already wrote a topic about the difficulty of managing global settings through multiple instances (a while ago).
I still hope someday I will be able to save myself the settings instead of a basic and automatic save at the end of instance. Each time I shutdown, I have to remember in which one I changed the settings to close it the last.

Lately, curveboolean command made me wonder about my old/previous request.
Few times in the last 2-3 weeks I use curveboolean and I lost all my settings (and the surface sidebar popped up). And not only in one instance, everyone. So, when I wanted to use the “not so obvious” method of closing the instance which has the good settings at last, I couldn’t. All instances were reset.

First, are there any development about multiple instance settings management ?
*** Second, anyone experiencing problems with curveboolean ?
*** It is not strictly related to curveboolean. I experienced the reset issue with pointson few days later.