problems with decimals

[TimSchofield]

Yes, sorry I see that now that I look properly at the code.
Can you comment out (add // to the start of the line) all 4 lines of that section:

if(isset($_POST['Qty' . $i]) AND trim($_POST['Qty' . $i]) != '' AND !is_numeric($_POST['Qty' . $i])) {
$InputError = true;
prnMsg(_('The quantity entered is not numeric - a number is expected'),'error');
}

Thanks
Tim