Thanks for the explanation...and the gratitude.
You should be able to select all the objects on the pages in your Publisher
file that will be printed upside down for folding, go to Arrange > Rotate or
Flip and rotate them 90 degrees, two times. Now those pages will appear
upside down on your Pub doc, but when you print to PDF all the pages will be
oriented the same. If you do this after you have saved all the changes you
have made to the Pub doc, and right before you are ready to close the Pub
doc, then just don't save the changes (the rotations) when you close, and
your document will remain correctly arranged for printing and folding, when
you open it again.
You need Publisher to open Publisher docs...no way around that. Your
collaborators could download and install the free trial version of Publisher
2007, and it would allow them to open and view Publisher docs, but not edit
them after the trial period. However, a Publisher document is usually a much
larger file than a PDF file....and a PDF file is also smaller than a JPG of
a page, so using the PDF option is the best in my opinion. If it were me, I
might put a temporary page number on each page so your helpers could
reference that page number with their comments.
Good luck.
DavidF