For regular RP files that get published to Axure Share via the "Publish to Axure Share" dialog, there isn't a way to view the generation dates and author names for previously uploaded versions of the file. I can go ahead and file this as a feature request to let the product management team know that there's interest in being able to see this information.
In the meantime, if you happen to be using the Team edition of Axure RP 8, then you could generate and view this information by creating your file as a team project hosted on Axure Share. Once your team project is hosted on Axure Share, you would publish changes to the Axure Share URL by checking in or sending changes to your team project. Checking in the changes leaves a record in the team project history, which allows you to view who checked in what changes and when. You can view the team project history by going to "Team > Browse Team Project History" to open the "Team Project History Browser" dialog. From here, you can browser your checkin history for the team project for all users, and you can export revisions to a RP file.
Hopefully this helps!