Somehow I couldn't get it to work.
I got the 'Cannot upload file: ' message, but there is no any error message.
Previously I created a folder on the server and gave 0755 as permission.
I have no idea. (Maybe missing user/pw)?
Update: you (GetMem) wrote this above: "For http(s) downloads, you will need the openssl libraries." Interestingly for the download it worked with my https without the openssl libraries. Maybe it is not the case for uploads?