Native iOS FileChooser Problem

I’ve some problems to make FileChooser using the OSNativeDialogBox to works in iOS
Browsing a file to open it
When attempt to copy the file using
in app documents folder or appGroup shared folder, for instance
I got this message:

The fileSrc couldn’t be opened because you don’t have permission to view it.

After few days I’ve discovered that the problem is related to the file, row 88

controller.reset ([controllerClassInstance initWithDocumentTypes: utTypeArray
                                                                      inMode: UIDocumentPickerModeOpen]);

changing UIDocumentPickerModeOpen in UIDocumentPickerModeImport
it works as aspected.

Since the browseForFileToOpen is generic, maybe it is better to change definitively in UIDocumentPickerModeImport?
Is there a reason why I cannot get to works the copying with UIDocumentPickerModeOpen?
Thank you, cheers.

Also the saveMode seems to does not work properly.
String suffix = “*.preset”;
String placeHolder = “MyPreset.preset”;

File destFile = File::getSpecialLocation(File::userDocumentsDirectory).getChildFile(placeHolder);
fc.reset(new FileChooser(TRANS("Save Preset"), destFile, suffix, true, false));

In the file, row 55
UIDocumentPickerMode pickerMode = currentFileOrDirectory.existsAsFile()
? UIDocumentPickerModeExportToService
: UIDocumentPickerModeMoveToService;

currentFileOrDirectory.existsAsFile() return NO, so I need to create a tmp file before destFile.create();
It is good? What is the difference UIDocumentPickerModeExportToService vs UIDocumentPickerModeMoveToService in this context?