Solveig,
they use V8.0. There's no specific list of scenarios.
One of the use cases that shows the behavior is copy&paste of a widget, change the name and click on some other widget. Most of the times, the new name is lost.
I've just tried with a radio button and a text input field.
Following the pattern: paste the widget - change the name - check and uncheck the "create inst var" checkbox, click on another widget helps prevent the loss of the name change. I guess you could also click on any other item on the toolbar instead of that checkbox...
Joachim