Hello James,
would you please check this code:

// RemoveDup
    function RemoveDup()
    {
        this.addInput("In", "objectlist");
        this.addInput("Tolerance", "numarray");
        this.addOutput("Out", "objectlist");
        this.properties = {Tolerance: [0.005]};
    }

    RemoveDup.title = "RemoveDupCrv";
    RemoveDup.desc = "RemoveDupCrv";

    RemoveDup.prototype.onExecute = function ()
    {
        var inObj = this.getInputData(0, moi.geometryDatabase.createObjectList());
        this.properties.Tolerance = this.getInputData(1, this.properties.Tolerance);
        var output = moi.geometryDatabase.createObjectList();
        var temp = moi.geometryDatabase.createObjectList();
        if (inObj.length > 0) {
            var tempname = getUID(6);
            for (var i = 0; i < inObj.length; i++)
                inObj.item(i).name = tempname;
            moi.geometryDatabase.addObjects(inObj);
            var fac = moi.command.createFactory('removeduplicates');
            fac.setInput(0, inObj);
            fac.setInput(1, this.properties.Tolerance[0]);
            inObj = moi.geometryDatabase.createObjectList();
            fac.commit();
            moi.geometryDatabase.selectNamed(tempname);
            temp = moi.geometryDatabase.getSelectedObjects();
            var originXYZ = moi.VectorMath.createPoint(0, 0, 0); //Helppoint for a identical copy
            output = factory('copy', temp, originXYZ, originXYZ, true);
            var delfac = moi.command.createFactory('delete');
            delfac.setInput(0, temp);
            delfac.commit();
        }
        this.setOutputData(0, output);
    };

    LiteGraph.registerNodeType("Objects2/RemoveDupCrv", RemoveDup);

Have a nice day
Karsten