Appending individual XML files to a sheet

I used Acrobat professional to send out a survey and the replies come back as
XML files. Although I'm fairly well acquainted with Excel, XML is very new
to me.

The XML files (I have about 150 replies) are idential in nature and contain
7 elements. When I import the first one, it creates the schema, but when I
import a second file it simply overwrites the data from the first. This
occurs whether the Overwrite or Append radio button is marked in XML Map
Properties.

I apparently don't know enoght about XML and importing them into a
spreadsheet, and I can certainly use some help. Thanks.