the files are in the C:\Program Files (x86)\BigFix Enterprise\BES Server\wwwrootbes\Uploads directory, organized by SHA1 (usually sort by date is the easiest way to find them).
edit: accidentally hit submit too soon.
We don’t currently support export and import, you’d need to re-import the files again on the second server using the same settings; you can use the files to verify that it’s happening correctly.