Will you please zip up your %LOCALAPPDATA%\Plex\Plex Media Server\Logs\ too? Your email description suggests to me that the part of Plex for Windows responsible for downloading is crashing and taking the rest of the app with it.
Your logs indicate that the download is being transcoded to a lower quality. Have you selected a Download Quality?
I can recreate this over and over. As soon as I add any file to my download list…Plex will crash. to get out of it, I have to QUICKLY click on downloads, while plex is loading and remove file from download queue. I have confirmed this same behavior on 3 separate computers.
I have not configured Plex to download low quality…just the opposite, I ask for high quality downloads.
@tannerjim will you please confirm you have sufficient disk space to download the video mentioned in your logs? Several of the log files mention that we were unable to retrieve the available disk space. When this happens we currently assume there is sufficient space and proceed. Perhaps this is the issue?