I am having a similar problem. I need to add multiple series to one chart and so I don't believe I can use the ChartWizard.

Currently, I use the following code to add a series:
$Chart->SeriesCollection->Add($Sheet3->Range("D$num2:D$num1"));

This however does not set the XValues, which I try to do with the following code:
$Range = $Sheet3->Range("C$num2:C$num1");
$Chart->SeriesCollection($series)->XValues($Range); ;

This results in the following error:
Win32::OLE(0.1709) error 0x80020011: "Does not support a collection"
in METHOD/PROPERTYGET "XValues" at ./PollenAVG.pl line 149

Any Ideas? Thank you in advance.