Reverting to original graphical representations of objects and relationships ?

Hi,
I would not use the script for this purpose because you will not be happy with the model alignment in the result. You would have to realign everything manually, at least to check those models. 
So there are two strategies:

1. To prevent, just take the method to change rights.
2. If it happens, I'd apply Restore as the default command for all changed objects. 

Thanks Alexander, there are hundreds of symbols whose representation should be updated. 

I finally managed  to do it using a script : 

var models = ArisData.getSelectedModels();
        for (var m in models)
        {
            var connectionOccurrences = 	models[m].CxnOccList();
            for (var c in connectionOccurrences) // reset connections style
            { 
                var connOcc = connectionOccurrences[c]
                connOcc.ResetLine();
                connOcc.setSourceArrow(0);  // reset default arrow . Aris doc is wrong , do not  use "-1" 
                connOcc.setTargetArrow(0);
            }
            var objectOccurrences = models[m].ObjOccList();
            for (var o in objectOccurrences)  // reset object styles
            {
                objectOccurrences[o].setDefaultProperties(true,false,false); // do not reset custom size nor color
            }