By Gianni Giaccaglini.
the "Attributes" problem is not so important: I found XPath filters they can solve it:
Set NodiXmlRif = DocXml.selectNodes("//sheetData/row/c[@t='s']/@r")
Set NodiXmlVal = DocXml.selectNodes("//sheetData/row/c[@t='s']/v")
These instructions refer to <c> (cell) tag of a sheet1.xml OOXML file. The filter [@t='s'] in this case selects only the c nodes with t property = "s", then the sub-nodes /@r and /v gives the reference property @r (e.g. "A1", "B1" etc.) and the values v, making it possible take into account the refs and the index (v) of sharedString.xml file.
All unfiltered nodes can be obtained by the following codes:
Set NodiXmlRif = DocXml.selectNodes("//sheetData/row/c/@r")
Set NodiXmlVal = DocXml.selectNodes("//sheetData/row/c/v")
, too; it is in italian but the entire routines in two version should be clear, I 'll hope)