Users will never find the sha256sums.txt file from the download page
https://trac.torproject.org/projects/tor/wiki/doc/TorBrowserBundle3FAQ#HowdoIverifythedownloadsha256sums.txt is great and all, but none of the download pages link to it in any way. We should sort out the right way to inform users about it.
To upload designs, you'll need to enable LFS and have an admin enable hashed storage. More information