It seems that safe item id and object names must be identical.
In case states are defined in the root level, there will be issues if those are not identical.
And the indicators example has different id and objectname for the safetext.
If those are different, then unhandled exception is thrown.
The exception is originated in <Src>\QtSafeRenderer-1.2.0\src\saferenderer\qsafelayout.cpp