I have a file which has been produced by exporting data from MS Project, and
I would like to make this easier to read in Excel by grouping Tasks and
sub-Tasks by Row. I don't have MS Project myself, so am dependant on
exports by people who do.

If I manually Group Tasks and sub-Tasks by Row can I copy/transfer these
Groups to the next version I receive, or do I have to do the grouping all
over again from scratch?

There is a column headed 'Outline Level', containing numbers 1 to 8. Can
these be used to create an Outline in Excel? If so how?