There is no program warning when using umlauts like ÄÖÜ for naming processes or models (and of course, umlauts should be usable).
When closing S3D then it is saving the actual settings in ...\AppData\Local\Simplify3D\S3D-Software\savedState.factory
But when S3D is started again aferwards, it throws a warning message "Failed to parse XML-File ... incorrectly encoded content"
and fails to correctly re-read the saved settings.
So it seems to me that storing parameters with non-standard characters in the xml factory files is somehow buggy.