The current production file size upload limit is 2GB. The documentation needs to be updated to reflect that. That said, this upper limit is a limitation of the upload control we're using. Until recently, there hasn't been much call for larger files. We have been investigating ways to handle very large files so we expect to improve this is an upcoming release.
There have been a few users who want to upload larger files, one recent user wanted to upload a single 100GB file. In most of those cases, the users were able to subdivide the file to sizes that did fit.
I would have to check with the group to provide an accurate answer but my impression was this was a limitation of file upload only.
Download should also be OK, but of course, the larger the file, the
more potential for the user to have to wait a long time , have the
download interrupted, etc.