I work crossplatform all the time and have never had an issue like that. Can you fill us in exactly on how you handled this?
FWIW, I use dropbox for this type of thing.
I’m a little hazy on what happened when going from Mac to Win, but very clear on returning to Mac: all graphic links were broken. Path to linked graphics went to c:\etc\etc, which of course does not work in Mac OS.
File names and folder names were, in general, still there, but I had to navigate manually to storage location(s) on the Mac, to show the O/S where the graphics were stored. As I said, after repeating this a few times, I found that nearly all of the rest were converted for me, automatically, by the O/S.
Like I said, I use Dropbox for this and have never run into it. If you moved things around this would be normal.
Did you package the file before moving it from Mac to Win and back again? If not, you should have.