Table error - invalid parameter

Hi Friends,

The below scripts provided by "vinny38", when i run the script its showing "invalid parameter" error, please see the screen shot below, i am beginner of this platform, anybody can guide to me:

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if (app.documents.length > 0) {

    var myDocument = app.documents[0];

    //----------------------------Open Dialog box----------------------------//

    var myStylesNames = [];

    for (i = 0; i < myDocument.allParagraphStyles.length; i++) {

        myStylesNames.push(myDocument.allParagraphStyles.name);

    }

    var myDialog = app.dialogs.add({

        name: "Align to dots script",

        canCancel: true

    });

    with(myDialog.dialogColumns.add()) {

        staticTexts.add({

            staticLabel: "Choose the paragraph style applied to the cells you want to align on dot"

        });

    }

    with(myDialog.dialogColumns.add()) {

        var myDDSTyles = dropdowns.add({   

            stringList: myStylesNames,

            selectedIndex: 0

        });

    }

    var myResult = myDialog.show();

    if (myResult == true) {

        var myParaStyle = myStylesNames[myDDSTyles.selectedIndex];

    }

    myDialog.destroy();

    //---------------------------- add a tab before (if doesn't exist)  ----------------------------//

    app.findGrepPreferences = null;

    app.changeGrepPreferences = null;

    app.findGrepPreferences.properties = {

        findWhat: "^(\\d)",

        appliedParagraphStyle: myParaStyle,

    }

    app.changeGrepPreferences.changeTo = "\\t$1";

    app.activeDocument.changeGrep();

    app.findGrepPreferences = null;

    app.changeGrepPreferences = null;

    //---------------------------- create array     ----------------------------//

    var myText = [];

    var allText = myDocument.stories.everyItem().tables.everyItem().cells.everyItem().paragraphs.everyItem().getElements();

    for (i = 0; i < allText.length; i++) {

        if (allText.appliedParagraphStyle.name == myParaStyle) {

            myText.push(allText);

        }

    }

    //---------------------------- Set tab alignment  and apply to cells   ----------------------------//

    var tabStopProperties = {

        alignment: TabStopAlignment.CHARACTER_ALIGN,

        alignmentCharacter: "."

    };

    for (var i = 0; i < myText.length; i++) {

        var cellWidth = myText.parent.width;

        var cellLeftInset = myText.parent.leftInset;

        var cellRightInset = myText.parent.rightInset;

        var position = (cellWidth - cellRightInset - cellLeftInset - 1.058) / 2;

        myText.tabStops.everyItem().remove();

        myText.tabStops.add();

        myText.tabStops[0].properties = tabStopProperties;

        myText.tabStops[0].position = position;

    }

} else {

    alert("Please open a document");

}

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Thanks

kanagakumar.k