I had this problem too... The example never worked on a standalone implementation... Here is the workaround I could come up with: jsFiddle
renderer : function(instance, td, row, col, prop, value) {
if (row == instance.countRows() - 1) {
value = parseFloat(document.getElementById("cellTotal").value);
} else {
setTotalValue(row, value);
}
Handsontable.renderers.NumericRenderer.apply(this, arguments);
Note that I have had to use a hidden placeholder to retain the sum of the column cells. May not be the best approach, but worked for me. Hoping that this would help saving precious time in working around the issue...
Tested with IE 10 and Chrome.