We are experiencing the same issue. We’re running 9.0.649.0.
We were able to resolve the problem in downloading external content by fixing the proxy settings on the BES Server, however, we cannot get custom content to download from the internal servers to our relays / endpoints.
If we use “download now” in the fixlet it forces the client to download directly from the source instead of trying to pull from their site relay, but that creates way too much network overhead. Using the standard “download” command we get errors and the download never completes.
It seems like this is a problem with the way the Relays handle internal addresses for content.