🚀 go-pugleaf

I'm trying to write a script that creates a table out of selected tab-delimited text and then applies various formatting to the resulting table. I can't seem to enable alternating row fills via script. I'm using InDesign CS on Windows XP. Here is the script that works OK, except that the alternating row fills are not implemented. What's the glitch that I'm missing?

textObj = app.selection[0];
mkTableFromText(textObj);

//FUNCTIONS
function mkTableFromText(textObj){
	with (textObj){
		leftIndent = 0;
		spaceBefore = "1p0";
		spaceAfter = "1p0";
		alignToBaseline = false;
	}
	iPt = textObj.insertionPoints[-1];
	iPt.contents = "\r";
	pFrame = iPt.parentTextFrame;
	tb = textObj.convertToTable("\t", "\r");
	tb.rows.lastItem().remove();
	coords = pFrame.geometricBounds;
	widOfpFrame = coords[3] - coords[1];
	formatTable(tb);
}

function formatTable(tb){
	with (tb){
		alternatingFills = AlternatingFillsTypes.alternatingRows;
		startRowFillColor = app.swatches.item("Black");
		startRowFillTint = 10;
		startRowFillCount = 1;
		skipFirstAlternatingFillRows = 0;
	}
	for (var i = 0; i < tb.rows.length; i++){
		r = tb.rows[i];
		with (r){
			width = widOfpFrame/tb.columnCount;
			bottomEdgeStrokeWeight = 0;
			topEdgeStrokeWeight = 0;
			leftEdgeStrokeWeight = 0;
			rightEdgeStrokeWeight = 0;
			innerColumnStrokeWeight = 0;
			leftInset = "0p5";
			rightInset = "0p5";
			topInset = "0p5";
			bottomInset = "0p5";
			minimumFirstBaselineOffset = "0p0";
		}
	}
	for(var i = 0; i < tb.cells.length; i++){
		c = tb.cells[i];
		if (c.parentColumn.index == 0) {
			c.texts[0].justification = 1818584692; //Justification.leftAlign
			c.verticalJustification = VerticalJustification.topAlign;
		}
		else {
			c.texts[0].justification = 1919379572; //Justification.rightAlign
			c.verticalJustification = VerticalJustification.bottomAlign;
		}
	}
}

Any light you can shed on this would be much appreciated. Thanks.
Matthew Mariani