You probably don't need to use Import/Export at all.
1> Run your tests once however you do it. Use Fiddler to capture the test running.
2> File > Save All Sessions. This will save the test requests in a SAZ file.
3> Later, to rerun the test, choose File > Load Archive and choose the SAZ file. All of the traffic will load.
4> Select all of the Sessions in the Web Sessions list (e.g. by clicking it and hitting CTRL+A)
5> Hit the "V" key on your keyboard. All of the Selected sessions will be replayed.
6> Amongst the results, you can sort the Result column to find any results which are not as expected (e.g. http/200).
You can easily copy those lines out to a program like Excel. Select them, right click, and choose "Copy > Full Summary"
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